drm/amdkfd: Fix memory reporting on GFX 9.4.3

This patch fixes memory reporting on the GFX 9.4.3 APU and dGPU
by reporting available memory on a per partition basis. If its an
APU, available and used memory calculations take into account
system and TTM memory.

v2: squash in fix ("drm/amdkfd: Fix array out of bound warning")
    squash in fix ("drm/amdgpu: Update memory reporting for GFX9.4.3")

Signed-off-by: Mukul Joshi <mukul.joshi@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>