Disable all display feature flags when there are no pipes i.e. there is
no display. This should help with not having to additionally check for
HAS_DISPLAY() when a feature flag check would suffice.

Also disable modeset and atomic driver features.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200910095227.9466-1-jani.nikula@intel.com