remove combined {models,sprites}.mat, remove extra .mdl .spr exts

valve/pbr/models/w_rpgammo.mdl/w_rpgammo.mat

@@ -0,0 +1,24 @@
+
+{
+"for" "#models/w_rpgammo/ammocan.mdl"
+//"basecolor_map" "ammocan.png"
+//"normal_map" "ammocan_normal.png"
+//"metal_map" "ammocan_metal.png"
+//"roughness_map" "ammocan_roughness.png"
+}
+
+{
+"for" "#models/w_rpgammo/ammocantop.mdl"
+//"basecolor_map" "ammocantop.png"
+//"normal_map" "ammocantop_normal.png"
+//"metal_map" "ammocantop_metal.png"
+//"roughness_map" "ammocantop_roughness.png"
+}
+
+{
+"for" "#models/w_rpgammo/rocket.mdl"
+//"basecolor_map" "rocket.png"
+//"normal_map" "rocket_normal.png"
+//"metal_map" "rocket_metal.png"
+//"roughness_map" "rocket_roughness.png"
+}