drm/amd/display: Remove BW Allocation from DPIA notification

drm/amd/display: Remove BW Allocation from DPIA notification

[Why]
USB4 BW Allocation response will be handled in HPD IRQ.
No need to handle it in DPIA notification callback.

[How]
Remove DP BW allocation response code in DPIA notification.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Cruise <Cruise.Hung@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>