ipv6: drop package name prefix from identifiers in docs for consistency

Change-Id: I842503c64b7b61913d0748cd5b5618543bcf198b
Reviewed-on: https://go-review.googlesource.com/34752
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

ipv6/doc.go

@@ -24,8 +24,8 @@
 // net.UDPConn and net.IPConn which are created as network connections
 // that use the IPv6 transport.  When a single TCP connection carrying
 // a data flow of multiple packets needs to indicate the flow is
-// important, ipv6.Conn is used to set the traffic class field on the
-// IPv6 header for each packet.
+// important, Conn is used to set the traffic class field on the IPv6
+// header for each packet.
 //
 //	ln, err := net.Listen("tcp6", "[::]:1024")
 //	if err != nil {
@@ -97,8 +97,8 @@
 // The application might set per packet control message transmissions
 // between the protocol stack within the kernel.  When the application
 // needs a destination address on an incoming packet,
-// SetControlMessage of ipv6.PacketConn is used to enable control
-// message transmissions.
+// SetControlMessage of PacketConn is used to enable control message
+// transmissions.
 //
 //	if err := p.SetControlMessage(ipv6.FlagDst, true); err != nil {
 //		// error handling