libperf: Add 'fd' to struct perf_mmap

Move 'fd' from tools/perf's mmap to libperf's perf_mmap struct.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lore.kernel.org/lkml/20190913132355.21634-13-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/lib/include/internal/mmap.h

@@ -10,6 +10,7 @@
 struct perf_mmap {
 	void		*base;
 	int		 mask;
+	int		 fd;
 };
 
 #endif /* __LIBPERF_INTERNAL_MMAP_H */