tools: Adopt __printf from kernel sources

To have a more compact way to ask the compiler to perform printf like
vargargs validation.

v2: Fixed up build on arm, squashing a patch by Kim Phillips, thanks!

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-dopkqmmuqs04cxzql0024nnu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/probe-event.h

@@ -1,6 +1,7 @@
 #ifndef _PROBE_EVENT_H
 #define _PROBE_EVENT_H
 
+#include <linux/compiler.h>
 #include <stdbool.h>
 #include "intlist.h"
 
@@ -171,8 +172,7 @@ void arch__fix_tev_from_maps(struct perf_probe_event *pev,
 			     struct symbol *sym);
 
 /* If there is no space to write, returns -E2BIG. */
-int e_snprintf(char *str, size_t size, const char *format, ...)
-	__attribute__((format(printf, 3, 4)));
+int e_snprintf(char *str, size_t size, const char *format, ...) __printf(3, 4);
 
 /* Maximum index number of event-name postfix */
 #define MAX_EVENT_INDEX	1024