src/pkg: fixed various typos

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7936043
diff --git a/src/pkg/net/udpsock_plan9.go b/src/pkg/net/udpsock_plan9.go
index 2a7e3d1..66dcbab 100644
--- a/src/pkg/net/udpsock_plan9.go
+++ b/src/pkg/net/udpsock_plan9.go
@@ -58,7 +58,7 @@
 }
 
 // ReadMsgUDP reads a packet from c, copying the payload into b and
-// the associdated out-of-band data into oob.  It returns the number
+// the associated out-of-band data into oob.  It returns the number
 // of bytes copied into b, the number of bytes copied into oob, the
 // flags that were set on the packet and the source address of the
 // packet.