s390/mm,fault: remove line break

chechpatch reports:

 CHECK: Alignment should match open parenthesis
 +               if (IS_ENABLED(CONFIG_PGSTE) && gmap &&
 +                       (flags & FAULT_FLAG_RETRY_NOWAIT)) {

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>