vfs: Make __fsync_super() a static function (version 4)

__fsync_super() does the same thing as fsync_super(). So change the only
caller to use fsync_super() and make __fsync_super() static. This removes
unnecessarily duplicated call to sync_blockdev() and prepares ground
for the changes to __fsync_super() in the following patches.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 931f6b8..fe47f72 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -241,7 +241,7 @@
 		sb->s_frozen = SB_FREEZE_WRITE;
 		smp_wmb();
 
-		__fsync_super(sb);
+		fsync_super(sb);
 
 		sb->s_frozen = SB_FREEZE_TRANS;
 		smp_wmb();