perf tools: Add gzip decompression support for kernel module

perf tools: Add gzip decompression support for kernel module

Now my Archlinux box shows module symbols correctly.

Before:
  $ perf report --stdio
  Failed to open /tmp/perf-3477.map, continuing without symbols
  no symbols found in /usr/bin/date, maybe install a debug package?
  No kallsyms or vmlinux with build-id 7b4ea0a49ae2111925857099aaf05c3246ff33e0 was found
  [drm] with build id 7b4ea0a49ae2111925857099aaf05c3246ff33e0 not found, continuing without symbols
  No kallsyms or vmlinux with build-id edd931629094b660ca9dec09a1b635c8d87aa2ee was found
  [jbd2] with build id edd931629094b660ca9dec09a1b635c8d87aa2ee not found, continuing without symbols
  No kallsyms or vmlinux with build-id a7b1eada671c34933e5610bb920b2ca4945a82c3 was found
  [ext4] with build id a7b1eada671c34933e5610bb920b2ca4945a82c3 not found, continuing without symbols
  No kallsyms or vmlinux with build-id d69511fa3e5840e770336ef45b06c83fef8d74e3 was found
  [scsi_mod] with build id d69511fa3e5840e770336ef45b06c83fef8d74e3 not found, continuing without symbols
  No kallsyms or vmlinux with build-id af0430af13461af058770ee9b87afc07922c2e77 was found
  [libata] with build id af0430af13461af058770ee9b87afc07922c2e77 not found, continuing without symbols
  No kallsyms or vmlinux with build-id aaeedff8160ce631a5f0333591c6ff291201d29f was found
  [libahci] with build id aaeedff8160ce631a5f0333591c6ff291201d29f not found, continuing without symbols
  No kallsyms or vmlinux with build-id c57907712becaf662dc4981824bb372c0441d605 was found
  [mac80211] with build id c57907712becaf662dc4981824bb372c0441d605 not found, continuing without symbols
  No kallsyms or vmlinux with build-id e0589077cc0ec8c3e4c40eb9f2d9e69d236bee8f was found
  [iwldvm] with build id e0589077cc0ec8c3e4c40eb9f2d9e69d236bee8f not found, continuing without symbols
  No kallsyms or vmlinux with build-id 2d86086bf136bf374a2f029cf85a48194f9b950b was found
  [cfg80211] with build id 2d86086bf136bf374a2f029cf85a48194f9b950b not found, continuing without symbols
  No kallsyms or vmlinux with build-id 4493c48599bdb3d91d0f8db5150e0be33fdd9221 was found
  [iwlwifi] with build id 4493c48599bdb3d91d0f8db5150e0be33fdd9221 not found, continuing without symbols
  ...
  #
  # Overhead  Command          Shared Object            Symbol
  # ........  ...............  .......................  ........................................................
  #
       0.03%  swapper          [ext4]                   [k] 0x000000000000fe2e
       0.03%  swapper          [kernel.kallsyms]        [k] account_entity_enqueue
       0.03%  swapper          [ext4]                   [k] 0x000000000000fc2b
       0.03%  irq/50-iwlwifi   [iwlwifi]                [k] 0x000000000000200b
       0.03%  swapper          [kernel.kallsyms]        [k] ktime_add_safe
       0.03%  swapper          [kernel.kallsyms]        [k] elv_completed_request
       0.03%  swapper          [libata]                 [k] 0x0000000000003997
       0.03%  swapper          [libahci]                [k] 0x0000000000001f25
       0.03%  swapper          [kernel.kallsyms]        [k] rb_next
       0.03%  swapper          [kernel.kallsyms]        [k] blk_finish_request
       0.03%  swapper          [ext4]                   [k] 0x0000000000010248
       0.00%  perf             [kernel.kallsyms]        [k] native_write_msr_safe

After:
  $ perf report --stdio
  Failed to open /tmp/perf-3477.map, continuing without symbols
  no symbols found in /usr/bin/tr, maybe install a debug package?
  ...
  #
  # Overhead  Command          Shared Object                Symbol
  # ........  ...............  ...........................  ......................................................
  #

       0.04%  kworker/u16:3    [ext4]                       [k] ext4_read_block_bitmap
       0.03%  kworker/u16:0    [mac80211]                   [k] ieee80211_sta_reset_beacon_monitor
       0.02%  irq/50-iwlwifi   [mac80211]                   [k] ieee80211_get_bssid
       0.02%  firefox          [e1000e]                     [k] __ew32_prepare
       0.02%  swapper          [libahci]                    [k] ahci_handle_port_interrupt
       0.02%  emacs            libglib-2.0.so.0.4000.0      [.] g_mutex_unlock
       0.02%  swapper          [e1000e]                     [k] e1000_clean_tx_irq
       0.02%  dwm              [kernel.kallsyms]            [k] __schedule
       0.02%  gnome-terminal-  [vdso]                       [.] __vdso_clock_gettime
       0.02%  swapper          [e1000e]                     [k] e1000_alloc_rx_buffers
       0.02%  irq/50-iwlwifi   [mac80211]                   [k] ieee80211_rx
       0.01%  firefox          [vdso]                       [.] __vdso_gettimeofday
       0.01%  irq/50-iwlwifi   [iwlwifi]                    [k] iwl_pcie_rxq_restock.part.13

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/87h9yexshi.fsf@sejong.aot.lge.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>