add blank material files

cstrike/pbr/models/p_smokegrenade.mdl/p_smokegrenade.mdl.mat

@@ -0,0 +1,16 @@
+
+{
+"for" "#models/p_smokegrenade/f_body.mdl"
+//"basecolor_map" "f_body.png"
+//"normal_map" "f_body_normal.png"
+//"metal_map" "f_body_metal.png"
+//"roughness_map" "f_body_roughness.png"
+}
+
+{
+"for" "#models/p_smokegrenade/f_top.mdl"
+//"basecolor_map" "f_top.png"
+//"normal_map" "f_top_normal.png"
+//"metal_map" "f_top_metal.png"
+//"roughness_map" "f_top_roughness.png"
+}