drm/i915/display/psr: Disable DC3CO when the PSR2 is used

Due to the changed sequence of activating/deactivating DC3CO, disable
DC3CO until the changed dc3co activating/deactivating sequence is applied.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/3134


Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210401170237.40472-1-gwan-gyeong.mun@intel.com