iommu_gas: eliminate unneeded wrappers

[alc]

Summary

Eliminate trivial wrappers for several iommu_gas functions. These wrappers serve no functional purpose.

Test Plan

Tested with netperf on amd64. On arm64, a kernel with the IOMMU option compiles.

[br]

The idea of these wrappers was to abstract function names, i.e. make them looking generic by removing name "gas". I'm not sure what "gas" stands for, but there is no such thing on arm64.

[br]

so with this I can use iommu_map() in my ARM Komeda display controller driver (part of cheribsd), not confusing anyone with 'gas'

sys/dev/drm/komeda/komeda_plane.c:      error = iommu_map(iodom,

[alc]

In D35487#804780, @br wrote:

The idea of these wrappers was to abstract function names, i.e. make them looking generic by removing name "gas". I'm not sure what "gas" stands for, but there is no such thing on arm64.

I believe that it stood for "guest address space".

I also considered renaming iommu_gas_map, etc. to iommu_map, etc., but that entailed more changes. Nonetheless, I would be happy to take that approach.

[br]

In D35487#804790, @alc wrote:

In D35487#804780, @br wrote:

The idea of these wrappers was to abstract function names, i.e. make them looking generic by removing name "gas". I'm not sure what "gas" stands for, but there is no such thing on arm64.

I believe that it stood for "guest address space".

I also considered renaming iommu_gas_map, etc. to iommu_map, etc., but that entailed more changes. Nonetheless, I would be happy to take that approach.

as you wish, I am more or less fine with 'guest address space' since it is not amd64-specific. But the approach would be good.