drm/amd/powerplay: Port vega10_didt_set_mask() to new macros

Start using new CGS bitmask macros.

Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>