Revert "drm/amd/display: Setup for mmhubbub3_warmup_mcif with big buffer"

This reverts commit 428542d9

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[WHY & HOW]
The writeback series cause a regression in thunderbolt display.

Signed-off-by: Alex Hung <alex.hung@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>