drm/i915: Flag purely internal commits to not clear crtc_state->inherited

If we have to force the hardware to go through a full modeset
due to eg. cdclk reprogramming, we need to preserve
crtc_state->inherited for all crtcs that have not otherwise
gone through the whole compute_config() stuff after connectors
have been detected.

Otherwise eg. cdclk induced modeset glk_force_audio_cdclk()
will clear the inherited flag, and thus the first real commit
coming from userspace later on will not be forced through
the full .compute_config() path and so eg. audio state may
not get properly recomputed.

But instead of adding all kinds of ad-hoc crtc_state->inherited
preservation hacks all over, let's change things so that we
only clear it for the crtcs directly included in userspace/client
initiated commits.

Should be far less fragile since now we just need to remember
to flag the internal commits, and not worry about where new
crtcs might get pulled in.

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5260
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230328122357.1697-1-ville.syrjala@linux.intel.com
Reviewed-by: Luca Coelho <luciano.coelho@intel.com>