add blank material files

valve/pbr/halflife.wad/+GENERIC_109/+GENERIC_109.mat

@@ -0,0 +1,16 @@
+
+{
+"for" "+0GENERIC_109"
+//"basecolor_map" "+0GENERIC_109.png"
+//"normal_map" "+0GENERIC_109_normal.png"
+//"metal_map" "+0GENERIC_109_metal.png"
+//"roughness_map" "+0GENERIC_109_roughness.png"
+}
+
+{
+"for" "+1GENERIC_109"
+//"basecolor_map" "+1GENERIC_109.png"
+//"normal_map" "+1GENERIC_109_normal.png"
+//"metal_map" "+1GENERIC_109_metal.png"
+//"roughness_map" "+1GENERIC_109_roughness.png"
+}