Somehow the intel_ddi_set_vc_payload_alloc(false) call has ended up
in ironlake_crtc_disable() rather than haswell_crtc_disable(). Move it
to the correct place.

intel_ddi_disable_transcoder_func() already disables the vc payload
allocation so this doesn't actually do anything more. The spec
says we should wait for some kind of ack after frobbing the bit. We
don't appear to do that currently, but if and when someone decides
that we should do it, intel_ddi_set_vc_payload_alloc() would appear
to be be the right place for it. So having the function call in
haswell_crtc_disable() seems like the right thing for the future
even if it does nothing currently.

Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>