drm/i915/psr: Add a FIXME for the PSR vs. AUX usage conflict

We need to disable PSR when we are doing AUX by hand, otherwise
it's possible that the PSR hardware could be using the AUX CH
while we try to do our manual stuff. Add a FIXME for now.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230411191429.29895-7-ville.syrjala@linux.intel.com


Reviewed-by: Jouni Högander <jouni.hogander@intel.com>