drm/amd/display: Fix Dynamic bpp issue with 8K30 with Navi 1X

Why:
In DCN2x, HW doesn't automatically divide MASTER_UPDATE_LOCK_DB_X
by the number of pipes ODM Combined.

How:
Set MASTER_UPDATE_LOCK_DB_X to the value that is adjusted by the
number of pipes ODM Combined.

Reviewed-by: Martin Leung <martin.leung@amd.com>
Acked-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Bing Guo <bing.guo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>