Fixes pounces targeting unliving on the landing turf (#4776)

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Fixes #1053

Stops pounce landing from scanning ghosts/holograms and targeting them
in place of a living target.

It was pretty obvious for Queen Eye but apparently seemed to actually
happen with Ghosts aswell - since there was no message due to checks
further down, it was overlooked

# Explain why it's good for the game
Invisible bugs aren't so fun


# Changelog
:cl:
fix: Fixed Ghosts and Queen Eye occasionally "eating" pounces in place
of a mob on the same turf.
/:cl:

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

@@ -357,8 +357,8 @@
 
 /mob/living/carbon/xenomorph/proc/pounced_turf(turf/T)
 	if(!T.density)
-		for(var/mob/M in T)
-			pounced_mob(M)
+		for(var/mob/living/mob in T)
+			pounced_mob(mob)
 			break
 	else
 		turf_launch_collision(T)