[MIRROR] EMP & Wires refactor (#12658)

Co-authored-by: Guti <32563288+TheCaramelion@users.noreply.github.com>
Co-authored-by: Cameron Lennox <killer65311@gmail.com>

code/modules/shieldgen/shield_generator.dm

@@ -8,7 +8,6 @@
 	icon_state = "generator0"
 	circuit = /obj/item/circuitboard/shield_generator
 	density = TRUE
-	var/datum/wires/shield_generator/wires = null
 	var/list/field_segments = list()    // List of all shield segments owned by this generator.
 	var/list/damaged_segments = list()  // List of shield segments that have failed and are currently regenerating.
 	var/shield_modes = 0                // Enabled shield mode flags
@@ -52,8 +51,7 @@
 
 /obj/machinery/power/shield_generator/Initialize(mapload)
 	. = ..()
-	if(!wires)
-		wires = new(src)
+	set_wires(new /datum/wires/shield_generator(src))
 	default_apply_parts()
 	connect_to_network()