s390x/flic: introduce inject_airq callback

Let's introduce a specialized way to inject adapter interrupts that,
unlike the common interrupt injection method, allows to take the
characteristics of the adapter into account.

For adapters subject to AIS facility:
- for non-kvm case, we handle the suppression for a given ISC in QEMU.
- for kvm case, we pass adapter id to kvm to do airq injection.

Add add tracepoint for suppressed airq and suppressing airq.

Signed-off-by: Yi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: Fei Li <sherrylf@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
