tools headers UAPI: Sync linux/fs.h with the kernel

tools headers UAPI: Sync linux/fs.h with the kernel

To pick up the changes in:

  c553ea4fdf27 ("fs/sync.c: sync_file_range(2) may use WB_SYNC_ALL writeback")

That should be used to beautify the 'sync_file_range' syscall 'flags'
arg.

This silences this perf build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
  diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-at3uoqcvmqdkwaysmvbj1wpv@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>