dev-amdgpu: Add VM class for apertures, TranslationGens

Create a VM class to reduce clutter in the amdgpu_device.* files. This
new file is in charge of reading/writting MMIOs related to VM contexts
and apertures. It also provides ranges checks for various apertures and
breaks out the MMIO interface so that there are not overloaded macro
definitions in the device MMIO methods.

The new translation generator classes for the various apertures are also
added to this class.

Change-Id: Ic224c1aa485685685b1136a46eed50bcf99d2350
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53066
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
7 files changed