fix targetOutput staying at 0 due to save before init

reactor.lua

@@ -164,9 +164,7 @@ function load_config()
 	sr.close()
 end
 
-if fs.exists("reactorconfig.txt") == false then
-	save_config()
-else
+if fs.exists("reactorconfig.txt") then
 	load_config()
 end
 
@@ -174,6 +172,8 @@ if not targetOutput then
 	targetOutput = fluxgate.getSignalLowFlow()
 end
 
+save_config()
+
 function reset()
 	term.clear()
 	term.setCursorPos(1,1)