drm/amd/display: Copy WM values from set A to other sets in hw_init

[Why]
When we transfer the WM range table to SMU, they can perform a watermark
switch right away. This can be a problem if we're in not in accelerated mode
during hw_init as SMU may initiate a dummy p-state change before the rest
of the watermarks are programmed. Watermark set A is defined to be
sufficient for all cases, so we can copy the values from set A to all other
sets, avoiding any issues from SMU doing WM switches.

[How]
 - new hubbub func init_watermarks
 - copy register values from set A to all other sets
 - call init_watermarks before calling notify_wm_ranges

Signed-off-by: Joshua Aberback <joshua.aberback@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Eryk Brol <eryk.brol@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>