Adds a few turf istype helpers (#20754)

* a very calming act
when the world is too much, too fast

* i'm tired
but i have to be efficient, infinite

* lick your lips at the sight of me
a fantasy made reality

code/game/objects/effects/alien_acid.dm

@@ -50,15 +50,15 @@
 			T.dump_contents()
 			qdel(target)
 
-		if(istype(target, /turf/closed/mineral))
+		if(ismineralturf(target))
 			var/turf/closed/mineral/M = target
 			M.ChangeTurf(M.baseturf)
 
-		if(istype(target, /turf/open/floor))
+		if(isfloorturf(target))
 			var/turf/open/floor/F = target
 			F.ChangeTurf(F.baseturf)
 
-		if(istype(target, /turf/closed/wall))
+		if(iswallturf(target))
 			var/turf/closed/wall/W = target
 			W.dismantle_wall(1)
 

code/game/objects/effects/contraband.dm

@@ -272,7 +272,7 @@ list(name = "- Carbon Dioxide", desc = " This informational poster teaches the v
 		if(!D)
 			return
 
-		if(istype(src,/turf/closed/wall) && user && user.loc == temp_loc)	//Let's check if everything is still there
+		if(iswallturf(src) && user && user.loc == temp_loc)	//Let's check if everything is still there
 			user << "<span class='notice'>You place the poster!</span>"
 		else
 			D.roll_and_drop(temp_loc,D.official)

code/game/objects/effects/effect_system/effects_smoke.dm

@@ -157,7 +157,7 @@
 	var/blast = 0
 
 /datum/effect_system/smoke_spread/freezing/proc/Chilled(atom/A)
-	if(istype(A,/turf/open))
+	if(isopenturf(A))
 		var/turf/open/T = A
 		if(T.air)
 			var/datum/gas_mixture/G = T.air