ksmbd: fix read of uninitialized variable ret in set_file_basic_info

Addresses-Coverity reported Uninitialized variables warninig :

/fs/ksmbd/smb2pdu.c: 5525 in set_file_basic_info()
5519                    if (!rc) {
5520                            inode->i_ctime = ctime;
5521                            mark_inode_dirty(inode);
5522                    }
5523                    inode_unlock(inode);
5524            }
>>>     CID 1506805:  Uninitialized variables  (UNINIT)
>>>     Using uninitialized value "rc".
5525            return rc;
5526     }
5527
5528     static int set_file_allocation_info(struct ksmbd_work *work,
5529                                 struct ksmbd_file *fp, char *buf)
5530     {

Addresses-Coverity: ("Uninitialized variable")
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>