perf mmap: Remove several unneeded includes from util/mmap.h

Those headers are not needed in util/mmap.h, remove them.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/mmap.h

@@ -2,18 +2,13 @@
 #define __PERF_MMAP_H 1
 
 #include <internal/mmap.h>
-#include <linux/compiler.h>
-#include <linux/refcount.h>
 #include <linux/types.h>
-#include <linux/ring_buffer.h>
 #include <linux/bitops.h>
 #include <perf/cpumap.h>
-#include <stdbool.h>
 #ifdef HAVE_AIO_SUPPORT
 #include <aio.h>
 #endif
 #include "auxtrace.h"
-#include "event.h"
 #include "util/compress.h"
 
 struct aiocb;