Make documentation match the source code.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@54379 65c4cc65-6c06-0410-ace0-fbb531ad65f3

configs/sip.conf.sample

@@ -132,7 +132,7 @@ srvlookup=yes			; Enable DNS SRV lookups on outbound calls
 				; for peers and users as well
 ;callevents=no			; generate manager events when sip ua 
 				; performs events (e.g. hold)
-;limitpeersonly=no		; Apply all call limits ("limit=") only to peers, never
+;limitonpeers=no		; Apply all call limits ("limit=") only to peers, never
 				; to users. This improves handling of call limits
 				; and device states in certain situations. The user part
 				; of a type=friend will still be affected by the call