drm/amdgpu: move iommu_resume before ip init/resume

Separate iommu_resume from kfd_resume, and move it before
other amdgpu ip init/resume.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=211277


Signed-off-by: James Zhu <James.Zhu@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org