drm/i915/psr: Pass intel_crtc_state instead of intel_dp in wait_for_idle

This is preparation to add own function for polling PSR being ready for
update when doing dsb commit.

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://lore.kernel.org/r/20250905072708.2659411-2-jouni.hogander@intel.com