Remove headers from iommu.h

[br]

Summary

Remove headers from iommu.h

Test Plan

boot amd64

[kib]

sys/dev/iommu/iommu_gas.c

72

This is quite weird #ifdef block. Why pci and iommu are under ifdef ?

sys/x86/iommu/intel_drv.c

72

I propose to make the order of headers consistent. Put dev/pci right after vm/, then dev/iommu, then x86 headers.

[br]

sys/x86/iommu/intel_drv.c

72

dev/iommu/busdma_iommu.h depends on struct bus_dma_tag_common, which is defined in x86/include/busdma_impl.h.
so x86 header should go first ?

[kib]

sys/x86/iommu/intel_drv.c

72

Might be. What provides a similar common structure on arm64 ?

[br]

Fix order of headers:
sys/vm/contrib/dev/machine/x86

[br]

sys/x86/iommu/intel_drv.c

72

arm64/include/bus_dma_impl.h