perf mmap: Introduce mmap_cpu_mask__duplicate()

This patch adds a new function in util/mmap.c to duplicate a mmap_cpu_mask.

This new function will be used in patches in the workqueue patchkit.

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/8943a548ef7a3dd3e015095afad7e9a8b2154c05.1629490974.git.rickyman7@gmail.com


[ bitmap_alloc() was renamed to bitmap_zalloc() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>