drm/i915/psr: Compute PSR entry_setup_frames into intel_crtc_state

drm/i915/psr: Compute PSR entry_setup_frames into intel_crtc_state

PSR entry_setup_frames is currently computed directly into struct
intel_dp:intel_psr:entry_setup_frames. This causes a problem if mode change
gets rejected after PSR compute config: Psr_entry_setup_frames computed for
this rejected state is in intel_dp:intel_psr:entry_setup_frame. Fix this by
computing it into intel_crtc_state and copy the value into
intel_dp:intel_psr:entry_setup_frames on PSR enable.

Fixes: 2b981d57e480 ("drm/i915/display: Support PSR entry VSC packet to be transmitted one frame earlier")
Cc: Mika Kahola <mika.kahola@intel.com>
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
Link: https://patch.msgid.link/20260312083710.1593781-3-jouni.hogander@intel.com
(cherry picked from commit 8c229b4aa00262c13787982e998c61c0783285e0)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>