Revert "[MIRROR] Replace all secondary flags with bitflags stored in the flags_2 var" (#2457)

ok you know what yeah i think i'll properly mirror https://github.com/Citadel-Station-13/Citadel-Station-13/pull/2411

code/modules/shuttle/shuttle.dm

@@ -178,7 +178,7 @@
 		var/turf/T = assigned_turfs[i]
 		if(T.type == turf_type)
 			T.ChangeTurf(/turf/open/space,/turf/open/space)
-			T.flags_1 |= UNUSED_TRANSIT_TURF_1
+			T.flags |= UNUSED_TRANSIT_TURF
 
 /obj/docking_port/stationary/transit/Destroy(force=FALSE)
 	if(force)

code/modules/shuttle/special.dm

@@ -61,7 +61,7 @@
 	var/obj/machinery/power/emitter/energycannon/magical/our_statue
 	var/list/mob/living/sleepers = list()
 	var/never_spoken = TRUE
-	flags_1 = NODECONSTRUCT_1
+	flags = NODECONSTRUCT
 
 /obj/structure/table/abductor/wabbajack/Initialize(mapload)
 	. = ..()
@@ -168,7 +168,7 @@
 	var/datum/job/captain/C = new /datum/job/captain
 	access_card.access = C.get_access()
 	access_card.access |= ACCESS_CENT_BAR
-	access_card.flags_1 |= NODROP_1
+	access_card.flags |= NODROP
 
 /mob/living/simple_animal/hostile/alien/maid/barmaid/Destroy()
 	qdel(access_card)
@@ -180,7 +180,7 @@
 
 /obj/structure/table/wood/bar
 	resistance_flags = LAVA_PROOF | FIRE_PROOF | ACID_PROOF
-	flags_1 = NODECONSTRUCT_1
+	flags = NODECONSTRUCT
 	max_integrity = 1000
 	var/boot_dir = 1