ext4: fix unbalanced up_write() in ext4_ext_truncate() error path

ext4_ext_truncate() should not invoke up_write(&EXT4_I(inode)->i_data_sem)
when ext4_orphan_add() returns an error, as it hasn't performed a
down_write() yet. This trivial patch fixes this by moving the up_write()
invocation above the out_stop label.
Signed-off-by: NEric Gouriou <egouriou@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/extents.c

@@ -3450,8 +3450,9 @@ void ext4_ext_truncate(struct inode *inode)
 	if (IS_SYNC(inode))
 		ext4_handle_sync(handle);
 
-out_stop:
 	up_write(&EXT4_I(inode)->i_data_sem);
+
+out_stop:
 	/*
 	 * If this was a simple ftruncate() and the file will remain alive,
 	 * then we need to clear up the orphan record which we created above.