[CIFS] Change semaphore to mutex for cifs lock_sem

Originally at http://lkml.org/lkml/2006/9/2/86

The recent change to "allow Windows blocking locks to be cancelled via a
CANCEL_LOCK call" introduced a new semaphore in struct cifsFileInfo,
lock_sem.  However, semaphores used as mutexes are deprecated these days,
and there's no reason to add a new one to the kernel.  Therefore, convert
lock_sem to a struct mutex (and also fix one indentation glitch on one of
the lines changed anyway).

Signed-off-by: Roland Dreier <roland@digitalvampire.org>
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index e4de8eb..23655de 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -311,7 +311,7 @@
 	/* lock scope id (0 if none) */
 	struct file * pfile; /* needed for writepage */
 	struct inode * pInode; /* needed for oplock break */
-	struct semaphore lock_sem;
+	struct mutex lock_mutex;
 	struct list_head llist; /* list of byte range locks we have. */
 	unsigned closePend:1;	/* file is marked to close */
 	unsigned invalidHandle:1;  /* file closed via session abend */