f2fs: remove i_sem lock coverage in f2fs_setxattr()

f2fs_inode.xattr_ver field was gone after commit d260081ccf
("f2fs: change recovery policy of xattr node block"), remove i_sem
lock coverage in f2fs_setxattr()

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/xattr.c

@@ -758,12 +758,9 @@ int f2fs_setxattr(struct inode *inode, int index, const char *name,
 	f2fs_balance_fs(sbi, true);
 
 	f2fs_lock_op(sbi);
-	/* protect xattr_ver */
-	down_write(&F2FS_I(inode)->i_sem);
 	down_write(&F2FS_I(inode)->i_xattr_sem);
 	err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags);
 	up_write(&F2FS_I(inode)->i_xattr_sem);
-	up_write(&F2FS_I(inode)->i_sem);
 	f2fs_unlock_op(sbi);
 
 	f2fs_update_time(sbi, REQ_TIME);