Add ancient debris as normal ore

mods/MAPGEN/mcl_mapgen_core/init.lua

@@ -404,6 +404,46 @@ if minetest.settings:get_bool("mcl_generate_ores", true) then
 		y_max          = mcl_worlds.layer_to_y(15),
 	})
 
+		--
+	-- Ancient debris
+	--
+	local ancient_debris_wherein = {"mcl_nether:netherrack","mcl_blackstone:blackstone","mcl_blackstone:basalt"}
+	-- Common spawn
+	minetest.register_ore({
+		ore_type       = "scatter",
+		ore            = "mcl_nether:ancient_debris",
+		wherein         = ancient_debris_wherein,
+		clust_scarcity = 25000, -- 0.004% chance
+		clust_num_ores = 3,
+		clust_size     = 3,
+		y_min = mcl_vars.mg_nether_min + 8,
+		y_max = mcl_vars.mg_nether_min + 22,
+	})
+
+		-- Rare spawn (below)
+	minetest.register_ore({
+		ore_type       = "scatter",
+		ore            = "mcl_nether:ancient_debris",
+		wherein         = ancient_debris_wherein,
+		clust_scarcity = 32000,
+		clust_num_ores = 2,
+		clust_size     = 3,
+		y_min = mcl_vars.mg_nether_min,
+		y_max = mcl_vars.mg_nether_min + 8,
+	})
+
+	-- Rare spawn (above)
+	minetest.register_ore({
+		ore_type       = "scatter",
+		ore            = "mcl_nether:ancient_debris",
+		wherein         = ancient_debris_wherein,
+		clust_scarcity = 32000,
+		clust_num_ores = 2,
+		clust_size     = 3,
+		y_min = mcl_vars.mg_nether_min + 22,
+		y_max = mcl_vars.mg_nether_min + 119,
+	})
+
 	--
 	-- Redstone
 	--