KVM: selftests: Add a self test for CMCI and UCNA emulations.

This patch add a self test that verifies user space can inject
UnCorrectable No Action required (UCNA) memory errors to the guest.
It also verifies that incorrectly configured MSRs for Corrected
Machine Check Interrupt (CMCI) emulation will result in #GP.

Signed-off-by: Jue Wang <juew@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220610171134.772566-9-juew@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>