s390/cio: remove duplicate struct ccw1 declaration

struct ccw1 is declared twice. One has been declared
at 21st line. Remove the duplicate.

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Acked-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>