go.net/ipv4: make RFC numbers in doc clickable on GoPkgDoc
R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/6591077
diff --git a/ipv4/doc.go b/ipv4/doc.go
index bfc6044..3ceb9d3 100644
--- a/ipv4/doc.go
+++ b/ipv4/doc.go
@@ -7,10 +7,10 @@
//
// The package provides IP-level socket options that allow
// manipulation of IPv4 facilities. The IPv4 and basic host
-// requirements for IPv4 are defined in RFC 791, 1112 and 1122. A
-// series of RFCs 2474, 2475, 2597, 2598 and 3168 describe how to use
-// the type-of-service field in a DiffServ, differentiated services
-// environment.
+// requirements for IPv4 are defined in RFC 791, RFC 1112 and RFC
+// 1122. A series of RFC 2474, RFC 2475, RFC 2597, RFC 2598 and RFC
+// 3168 describe how to use the type-of-service field in a DiffServ,
+// differentiated services environment.
//
//
// Unicasting
