tools include: Adopt linux/bits.h

So that we reduce the difference of tools/include/linux/bitops.h to the
original kernel file, include/linux/bitops.h, trying to remove the need
to define BITS_PER_LONG, to avoid clashes with asm/bitsperlong.h.

And the things removed from tools/include/linux/bitops.h are really in
linux/bits.h, so that we can have a copy and then
tools/perf/check_headers.sh will tell us when new stuff gets added to
linux/bits.h so that we can check if it is useful and if any adjustment
needs to be done to the tools/{include,arch}/ copies.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-y1sqyydvfzo0bjjoj4zsl562@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/check-headers.sh

@@ -14,6 +14,7 @@ include/uapi/linux/sched.h
 include/uapi/linux/stat.h
 include/uapi/linux/vhost.h
 include/uapi/sound/asound.h
+include/linux/bits.h
 include/linux/hash.h
 include/uapi/linux/hw_breakpoint.h
 arch/x86/include/asm/disabled-features.h