ocfs2: Remove EXIT from masklog.

mlog_exit is used to record the exit status of a function.
But because it is added in so many functions, if we enable it,
the system logs get filled up quickly and cause too much I/O.
So actually no one can open it for a production system or even
for a test.

This patch just try to remove it or change it. So:
1. if all the error paths already use mlog_errno, it is just removed.
   Otherwise, it will be replaced by mlog_errno.
2. if it is used to print some return value, it is replaced with
   mlog(0,...).
mlog_exit_ptr is changed to mlog(0.
All those mlog(0,...) will be replaced with trace events later.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>

fs/ocfs2/xattr.c

@@ -5570,7 +5570,6 @@ static int ocfs2_xattr_set_entry_bucket(struct inode *inode,
 
 
 out:
-	mlog_exit(ret);
 	return ret;
 }
 
@@ -5637,7 +5636,6 @@ static int ocfs2_xattr_set_entry_index_block(struct inode *inode,
 		mlog_errno(ret);
 
 out:
-	mlog_exit(ret);
 	return ret;
 }