perf fs: Rename NAME_find_mountpoint() to NAME__mountpoint()

Shorten it, "finding" it is an implementation detail, what callers want
is the pathname, not to ask for it to _always_ do the lookup.

And the existing implementation already caches it, i.e. it doesn't
"finds" it on every call.

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-r24wa4bvtccg7mnkessrbbdj@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 45b42df..c232d8d 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -77,9 +77,8 @@
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -166,9 +165,8 @@
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -212,11 +210,10 @@
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
 	FILE *file;
 	int ret = 0;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return -1;
 
@@ -241,11 +238,10 @@
 static void pmu_read_sysfs(void)
 {
 	char path[PATH_MAX];
-	const char *sysfs;
 	DIR *dir;
 	struct dirent *dent;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return;
 
@@ -270,11 +266,10 @@
 {
 	struct stat st;
 	char path[PATH_MAX];
-	const char *sysfs;
 	FILE *file;
 	struct cpu_map *cpus;
+	const char *sysfs = sysfs__mountpoint();
 
-	sysfs = sysfs_find_mountpoint();
 	if (!sysfs)
 		return NULL;