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

Picking the changes from:

  3632679 ("ipv{4,6}/raw: fix output xfrm lookup wrt protocol")

That includes a define (IP_PROTOCOL) that isn't being used in generating
any id -> string table used by 'perf trace'.

Addresses this 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: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/lkml/ZHD/Ms0DMq7viaq+@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/uapi/linux/in.h

@@ -163,6 +163,7 @@ struct in_addr {
 #define IP_MULTICAST_ALL		49
 #define IP_UNICAST_IF			50
 #define IP_LOCAL_PORT_RANGE		51
+#define IP_PROTOCOL			52
 
 #define MCAST_EXCLUDE	0
 #define MCAST_INCLUDE	1