perf tools: Remove util.h from where it is not needed

Check that it is not needed and remove, fixing up some fallout for
places where it was only serving to get something else.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-9h6dg6lsqe2usyqjh5rrues4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/mmap-thread-lookup.c

@@ -14,7 +14,7 @@
 #include "map.h"
 #include "symbol.h"
 #include "thread.h"
-#include "util.h"
+#include "util.h" // page_size
 
 #define THREADS 4