This fixes the detection of pending interrupts when pirval is 0 and the
pending bit is set
More information how this situation occurs, can be found here:
c5b5f2d808/sys/amd64/vmm/intel/vmx.c (L4016-L4031)
Reviewed by: corvink, markj
Fixes: 02cc877968 ("Recognize a pending virtual interrupt while emulating the halt instruction.")
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D39620