tools headers uapi: Update linux/in.h copy

To get the changes in:

  4effd28c ("bridge: join all-snoopers multicast address")

That do not generate any changes in tools/ use of this file.

Silences this tools/perf build warning:

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

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Linus Lüssing <linus.luessing@c0d3.blue>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-ifpl634035266ho6wxuqgo81@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>