perf tools: Stop using 'self' in some more places

As suggested by tglx, 'self' should be replaced by something that is
more useful.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-fmblhc6tbb99tk1q8vowtsbj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 7ded71d..a92770c 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -89,14 +89,14 @@
 	return raw - build_id;
 }
 
-char *dso__build_id_filename(struct dso *self, char *bf, size_t size)
+char *dso__build_id_filename(struct dso *dso, char *bf, size_t size)
 {
 	char build_id_hex[BUILD_ID_SIZE * 2 + 1];
 
-	if (!self->has_build_id)
+	if (!dso->has_build_id)
 		return NULL;
 
-	build_id__sprintf(self->build_id, sizeof(self->build_id), build_id_hex);
+	build_id__sprintf(dso->build_id, sizeof(dso->build_id), build_id_hex);
 	if (bf == NULL) {
 		if (asprintf(&bf, "%s/.build-id/%.2s/%s", buildid_dir,
 			     build_id_hex, build_id_hex + 2) < 0)