perf tools: Convert open coded equivalents to asprintf()

The following snippet
	V = malloc(S);
	if (!V) { }
	sprintf(V, ...)

Can be easily changed to a one line:

	if (asprintf(&V, ...) < 0) { }

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Link: http://lkml.kernel.org/r/1404474229-15272-1-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index 95aefa7..e4132ae 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -333,12 +333,9 @@
 	if (!debugfs)
 		return NULL;
 
-	tracing = malloc(strlen(debugfs) + 9);
-	if (!tracing)
+	if (asprintf(&tracing, "%s/tracing", debugfs) < 0)
 		return NULL;
 
-	sprintf(tracing, "%s/tracing", debugfs);
-
 	tracing_found = 1;
 	return tracing;
 }
@@ -352,11 +349,9 @@
 	if (!tracing)
 		return NULL;
 
-	file = malloc(strlen(tracing) + strlen(name) + 2);
-	if (!file)
+	if (asprintf(&file, "%s/%s", tracing, name) < 0)
 		return NULL;
 
-	sprintf(file, "%s/%s", tracing, name);
 	return file;
 }