tools headers: Synchronize linux/bits.h with the kernel sources

To pick up the changes in this cset:

   3c7a8e190b ("uapi: introduce uapi-friendly macros for GENMASK")

That just causes perf to rebuild. Its just some macros going to an uapi
header that we now have to grab a copy into tools/ as well.

This addresses this perf build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/include/linux/bits.h include/linux/bits.h

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/lkml/ZiwJsFOBez0MS4r9@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/uapi/asm-generic/bitsperlong.h

@@ -24,4 +24,8 @@
 #endif
 #endif
 
+#ifndef __BITS_PER_LONG_LONG
+#define __BITS_PER_LONG_LONG 64
+#endif
+
 #endif /* _UAPI__ASM_GENERIC_BITS_PER_LONG */