Fix broken iron armor images

mods/minetest-3d_armor/3d_armor/init.lua

@@ -11,7 +11,7 @@ minetest.register_tool("3d_armor:helmet_leather", {
 
 minetest.register_tool("3d_armor:helmet_iron", {
 	description = "Iron Helmet",
-	inventory_image = "3d_armor_inv_helmet_steel.png",
+	inventory_image = "3d_armor_inv_helmet_iron.png",
 	groups = {armor_head=10, armor_heal=5, armor_use=250},
 	wear = 0,
 })
@@ -48,7 +48,7 @@ minetest.register_tool("3d_armor:chestplate_leather", {
 
 minetest.register_tool("3d_armor:chestplate_iron", {
 	description = "Iron Chestplate",
-	inventory_image = "3d_armor_inv_chestplate_steel.png",
+	inventory_image = "3d_armor_inv_chestplate_iron.png",
 	groups = {armor_torso=20, armor_heal=5, armor_use=250},
 	wear = 0,
 })
@@ -85,7 +85,7 @@ minetest.register_tool("3d_armor:leggings_leather", {
 
 minetest.register_tool("3d_armor:leggings_iron", {
 	description = "Iron Leggings",
-	inventory_image = "3d_armor_inv_leggings_steel.png",
+	inventory_image = "3d_armor_inv_leggings_iron.png",
 	groups = {armor_legs=15, armor_heal=5, armor_use=250},
 	wear = 0,
 })
@@ -121,7 +121,7 @@ minetest.register_tool("3d_armor:boots_leather", {
 
 minetest.register_tool("3d_armor:boots_iron", {
 	description = "Iron Boots",
-	inventory_image = "3d_armor_inv_boots_steel.png",
+	inventory_image = "3d_armor_inv_boots_iron.png",
 	groups = {armor_feet=10, armor_heal=5, armor_use=250},
 	wear = 0,
 })