perf tools: Add missing util.h to pick up 'page_size' variable

Not to depend of getting it indirectly.

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-tirjsmvu4ektw0k7lm8k9lhu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/x86/util/intel-pt.c

@@ -25,6 +25,7 @@
 #include "../../util/auxtrace.h"
 #include "../../util/tsc.h"
 #include "../../util/intel-pt.h"
+#include "../../util/util.h"
 
 #define KiB(x) ((x) * 1024)
 #define MiB(x) ((x) * 1024 * 1024)