ocfs2: unlock rw lock if inode lock failed

ocfs2: unlock rw lock if inode lock failed

In ocfs2_file_aio_write(), it does ocfs2_rw_lock() first and then
ocfs2_inode_lock().

But if ocfs2_inode_lock() failed, it goes to out_sems without unlocking
rw lock.  This will cause a bug in ocfs2_lock_res_free() when testing
res->l_ex_holders, which is increased in __ocfs2_cluster_lock() and
decreased in __ocfs2_cluster_unlock().

Signed-off-by: Joseph Qi <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: "Duyongfeng (B)" <[email protected]>
Acked-by: Sunil Mushran <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>