The auxtrace.h header references BITS_PER_LONG without including the
header where it is defined, getting it by luck from some other header,
fix it.

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-v04ydmbh7tvpcctf3zld9j9s@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>