Revert "drm/amd/display: Don't allow IPS2 in D0 for RCG Dynamic"

This reverts commit 84886469.

In some test environments causes reporting failures for S0i3/S4.

It shouldn't actually block entry provided there's no race with the
last state being updated, but currently suspecting there's an IPS2
check that's no longer being met.

Fixes: 84886469 ("drm/amd/display: Don't allow IPS2 in D0 for RCG Dynamic")
Reviewed-by: Ovidiu Bunea <ovidiu.bunea@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@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>