Remove unused (and ifdef'd) unp_abort() and unp_drain().

MFC after:	1 month

sys/kern/uipc_usrreq.c

@@ -1039,16 +1039,6 @@ unp_disconnect(struct unpcb *unp)
 	}
 }
 
-#ifdef notdef
-void
-unp_abort(struct unpcb *unp)
-{
-
-	unp_detach(unp);
-	UNP_UNLOCK_ASSERT();
-}
-#endif
-
 /*
  * unp_pcblist() assumes that UNIX domain socket memory is never reclaimed
  * by the zone (UMA_ZONE_NOFREE), and as such potentially stale pointers
@@ -1190,14 +1180,6 @@ unp_drop(struct unpcb *unp, int errno)
 	unp_disconnect(unp);
 }
 
-#ifdef notdef
-void
-unp_drain(void)
-{
-
-}
-#endif
-
 static void
 unp_freerights(struct file **rp, int fdcount)
 {