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

gearbox/pbr/models/v_penguin.mdl/v_penguin.mat

@@ -0,0 +1,24 @@
+
+{
+"for" "#models/v_penguin/hand.mdl"
+//"basecolor_map" "hand.png"
+//"normal_map" "hand_normal.png"
+//"metal_map" "hand_metal.png"
+//"roughness_map" "hand_roughness.png"
+}
+
+{
+"for" "#models/v_penguin/penguin_reference.mdl"
+//"basecolor_map" "penguin_reference.png"
+//"normal_map" "penguin_reference_normal.png"
+//"metal_map" "penguin_reference_metal.png"
+//"roughness_map" "penguin_reference_roughness.png"
+}
+
+{
+"for" "#models/v_penguin/skin.mdl"
+//"basecolor_map" "skin.png"
+//"normal_map" "skin_normal.png"
+//"metal_map" "skin_metal.png"
+//"roughness_map" "skin_roughness.png"
+}