drm/i915/joiner: Make joiner "nomodeset" state copy independent of pipe order

drm/i915/joiner: Make joiner "nomodeset" state copy independent of pipe order

Currently the joiner primary->secondary hw state copy still happens from
the main compute_config loop alongside the primary uapi->hw state copy.
The primary uapi->hw state copy must therefore happen first, or else
we'll end up copying stale junk into the secondary.

We have a WARN in intel_atomic_check_joiner() to make sure the CRTCs
will be walked in the correct order. The plan is to reoder the CRTCs,
which would mess up the order, unless we also adjust the iterators
to keep the pipe order. The actual plan is to do both, so technically
we should be able to just remove the WARN and call it a day.

But relying on the iteration order like this is fragile and confusing,
so let's move the "nomodeset" joiner state copy into the later loop
where the "modeset" state copy is also done. The first loop having
completely finished, we are guaranteed to have up to date hw state
on the primary when we do the copy to the secondary.

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patch.msgid.link/20260408155744.13326-2-ville.syrjala@linux.intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>