pci: Cosmetic cleanups to MSI/MSI-X routines

[jhb]

Summary

• Use unsigned integers for various variables. The count argument to the alloc method as well as the IRQ values used with the pcib_if.m methods should also be unsigned eventually.

• Use mallocarray to allocate arrays

• Use bool in a few places

[krzysztof.galazka_intel.com]

sys/dev/pci/pci.c

2023

Have you considered using bitstring instead?