drm/i915/psr: Use enable boolean from intel_crtc_state for Early Transport

When enabling Early Transport use
intel_crtc_state->enable_psr2_su_region_et instead of
psr2_su_region_et_valid.
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Fixes: 467e4e06 ("drm/i915/psr: Enable psr2 early transport as possible")
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240529093849.1016172-4-jouni.hogander@intel.com

drivers/gpu/drm/i915/display/intel_psr.c

@@ -710,7 +710,7 @@ void intel_psr_enable_sink(struct intel_dp *intel_dp,
 					   DP_ALPM_ENABLE |
 					   DP_ALPM_LOCK_ERROR_IRQ_HPD_ENABLE);
 
-			if (psr2_su_region_et_valid(intel_dp))
+			if (crtc_state->enable_psr2_su_region_et)
 				dpcd_val |= DP_PSR_ENABLE_SU_REGION_ET;
 		}