add blank material files

valve/pbr/halflife.wad/+ELEV_UP/+ELEV_UP.mat

@@ -0,0 +1,16 @@
+
+{
+"for" "+0ELEV_UP"
+//"basecolor_map" "+0ELEV_UP.png"
+//"normal_map" "+0ELEV_UP_normal.png"
+//"metal_map" "+0ELEV_UP_metal.png"
+//"roughness_map" "+0ELEV_UP_roughness.png"
+}
+
+{
+"for" "+AELEV_UP"
+//"basecolor_map" "+AELEV_UP.png"
+//"normal_map" "+AELEV_UP_normal.png"
+//"metal_map" "+AELEV_UP_metal.png"
+//"roughness_map" "+AELEV_UP_roughness.png"
+}