add blank material files

valve/pbr/halflife.wad/+LAB1_W6A/+LAB1_W6A.mat

@@ -0,0 +1,8 @@
+
+{
+"for" "+ALAB1_W6A"
+//"basecolor_map" "+ALAB1_W6A.png"
+//"normal_map" "+ALAB1_W6A_normal.png"
+//"metal_map" "+ALAB1_W6A_metal.png"
+//"roughness_map" "+ALAB1_W6A_roughness.png"
+}