s390x: smp: Test local interrupts after cpu reset

Local interrupts (external and emergency call) should be cleared after
any cpu reset.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200429143518.1360468-5-frankja@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>