Remove binary radio message from description

Binary speak ( :b ) was removed from positronic brains, but the message sent to players when initially becoming one still said that they could use it. I've gone ahead and removed that line of the message so people won't get confused.

code/modules/mob/living/carbon/brain/posibrain.dm

@@ -98,7 +98,6 @@
 	src.brainmob << "<b>You are a positronic brain, brought into existence on [station_name()].</b>"
 	src.brainmob << "<b>As a synthetic intelligence, you answer to all crewmembers, as well as the AI.</b>"
 	src.brainmob << "<b>Remember, the purpose of your existence is to serve the crew and the station. Above all else, do no harm.</b>"
-	src.brainmob << "<b>Use say :b to speak to other artificial intelligences.</b>"
 	src.brainmob.mind.assigned_role = "Positronic Brain"
 
 	var/turf/T = get_turf_or_move(src.loc)
@@ -200,4 +199,4 @@
 
 /obj/item/device/mmi/posibrain/ipc
 	desc = "A cube of shining metal, four inches to a side and covered in shallow grooves. The speaker switch is set to 'off'."
-	silenced = 1
+	silenced = 1