ksmbd: Change the return value of ksmbd_vfs_query_maximal_access to void

The return value of ksmbd_vfs_query_maximal_access is meaningless,
it is better to modify it to void.

Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>