perf record: Make --buildid-mmap the default

perf record: Make --buildid-mmap the default

Support for build IDs in mmap2 perf events has been present since
Linux v5.12:
https://lore.kernel.org/lkml/20210219194619.1780437-1-acme@kernel.org/
Build ID mmap events don't avoid the need to inject build IDs for DSO
touched by samples as the build ID cache is populated by perf
record. They can avoid some cases of symbol mis-resolution caused by
the file system changing from when a sample occurred and when the DSO
is sought.

Unlike the --buildid-mmap option, this chnage doesn't disable the
build ID cache but it does disable the processing of samples looking
for DSOs to inject build IDs for. To disable the build ID cache the -B
(--no-buildid) option should be used.

Making this option the default was raised on the list in:
https://lore.kernel.org/linux-perf-users/CAP-5=fXP7jN_QrGUcd55_QH5J-Y-FCaJ6=NaHVtyx0oyNh8_-Q@mail.gmail.com/

Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250724163302.596743-9-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>