s390x: move sclp_service_call() to sclp.h

Implemented in sclp.c, so let's move it to the right include file.
Also adjust some includes.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170913132417.24384-9-david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
3 files changed