vfio-ccw: make vfio_ccw_regops variables declarations static

Fixes the following sparse warnings:
drivers/s390/cio/vfio_ccw_chp.c:62:30: warning: symbol 'vfio_ccw_schib_region_ops' was not declared. Should it be static?
drivers/s390/cio/vfio_ccw_chp.c:117:30: warning: symbol 'vfio_ccw_crw_region_ops' was not declared. Should it be static?

Link: https://lkml.kernel.org/r/patch.git-a34be7aede18.your-ad-here.call-01591269421-ext-5655@work.hours


Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>