Ceiling lighting fix

The ceiling lighting linedef special (and anything else that changes ceiling lighting directly for sectors) works in software mode now.

src/r_segs.c

@@ -1922,7 +1922,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
|| backsector->ceilingpic_angle != frontsector->ceilingpic_angle
//SoM: 3/22/2000: Prevents bleeding.
|| (frontsector->heightsec != -1 && frontsector->ceilingpic != skyflatnum)
-		    || backsector->floorlightsec != frontsector->floorlightsec
+		    || backsector->ceilinglightsec != frontsector->ceilinglightsec
//SoM: 4/3/2000: Check for colormaps
|| frontsector->extra_colormap != backsector->extra_colormap
|| (frontsector->ffloors != backsector->ffloors && frontsector->tag != backsector->tag))