f2fs: move error condition for mkdir at proper place

In function f2fs_mkdir, err is being initialized without even checking
if there was any error in new inode creation. So, instead check the
inode error and make use of error/return condition.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>

fs/f2fs/namei.c

@@ -287,9 +287,8 @@ static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 	int err;
 
 	inode = f2fs_new_inode(dir, S_IFDIR | mode);
-	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
-		return err;
+		return PTR_ERR(inode);
 
 	inode->i_op = &f2fs_dir_inode_operations;
 	inode->i_fop = &f2fs_dir_operations;