drm/i915: Reject excessive dotclocks early

drm/i915: Reject excessive dotclocks early

Make sure modes with crazy big dotclocks are rejected early,
so as to not cause problems for subsequent code via integer
overflows and whatnot.

These would eventually be rejected in intel_crtc_compute_pipe_mode()
but that is now too late as we do the clock computations a bit
earlier than that. And we don't want to just reorder the two since
we still want to check the final computed dotclock against the
hardware limit to make sure we didn't end up above the limit due
to rounding/etc.

Fixes: 0ff0e219d9b8 ("drm/i915: Compute clocks earlier")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220927182455.3422-1-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>