fs/fscache/stats.c: fix memory leak

There is a kernel memory leak observed when the proc file
/proc/fs/fscache/stats is read.

The reason is that in fscache_stats_open, single_open is called and the
respective release function is not called during release.  Hence fix
with correct release function - single_release().

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=57101

Signed-off-by: Anurup m <[email protected]>
Cc: shyju pv <[email protected]>
Cc: Sanil kumar <[email protected]>
Cc: Nataraj m <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: David Howells <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

fs/fscache/stats.c

@@ -287,5 +287,5 @@ const struct file_operations fscache_stats_fops = {
 	.open		= fscache_stats_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
-	.release	= seq_release,
+	.release        = single_release,
 };