Fix xeno gib remains (#8232)

# About the pull request
Was broken by decal burning
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# Explain why it's good for the game
Fixes a bug
# Testing Photographs and Procedure
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<summary>Screenshots & Videos</summary>

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# Changelog
:cl:
fix: Fixed xeno gib remains not appearing
/:cl:

code/game/objects/effects/decals/remains.dm

@@ -16,6 +16,14 @@
 	anchored = TRUE
 	layer = BELOW_OBJ_LAYER
 
+/obj/effect/decal/remains/xeno/Initialize(mapload, icon, icon_state, pixel_x)
+	. = ..()
+
+	src.icon = icon
+	src.icon_state = icon_state
+	src.pixel_x = pixel_x
+
+
 /obj/effect/decal/remains/robot
 	name = "remains"
 	desc = "They look like the remains of something mechanical. They have a strange aura about them."

code/modules/mob/living/carbon/xenomorph/death.dm

@@ -150,10 +150,7 @@
 			no_remains = TRUE
 
 	if(!no_remains)
-		var/obj/effect/decal/remains/xeno/remains = new(get_turf(src))
-		remains.pixel_x = pixel_x //For 2x2.
-		remains.icon_state = "gibbed-a-corpse"
-		remains.icon = icon
+		new /obj/effect/decal/remains/xeno(get_turf(src), icon, "gibbed-a-corpse", pixel_x)
 
 	check_blood_splash(35, BURN, 65, 2) //Some testing numbers. 35 burn, 65 chance.