drm/i915: Move hw.active assignment into intel_crtc_get_pipe_config()

No reason to make the callers of intel_crtc_get_pipe_config()
populate hw.active. Let's do it in intel_crtc_get_pipe_config()
itself. hw.enable we leave up to the callers since it's slightly
different for readout vs. state check.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201112191718.16683-4-ville.syrjala@linux.intel.com