drm: Add for_each_oldnew_intel_crtc_in_state_reverse()

drm: Add for_each_oldnew_intel_crtc_in_state_reverse()

Same as for_each_oldnew_intel_crtc_in_state() but iterates in reverse
order.

v2: Fix additional blank line
v3: Rebase

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823082055.5992-12-lucas.demarchi@intel.com