drm/amdgpu: update mmhub mgcg&ls for mmhub_v2_3

Starting from vangogh, the ATCL2 and DAGB0 registers relative
to mgcg/ls has changed.

For MGCG:
Replace mmMM_ATC_L2_MISC_CG with mmMM_ATC_L2_CGTT_CLK_CTRL.

For MGLS:
Replace mmMM_ATC_L2_MISC_CG with mmMM_ATC_L2_CGTT_CLK_CTRL.
Add DAGB0_(WR/RD)_CGTT_CLK_CTRL registers.

Signed-off-by: Aaron Liu <aaron.liu@amd.com>
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>