net: replace error variable name e, errno with err

R=rsc, r
CC=golang-dev
https://golang.org/cl/5593046
diff --git a/src/pkg/net/multicast_test.go b/src/pkg/net/multicast_test.go
index 183d5a8..b6a2fa6 100644
--- a/src/pkg/net/multicast_test.go
+++ b/src/pkg/net/multicast_test.go
@@ -42,10 +42,6 @@
 	}
 
 	for _, tt := range multicastUDPTests {
-		var (
-			ifi   *Interface
-			found bool
-		)
 		if tt.ipv6 && (!supportsIPv6 || os.Getuid() != 0) {
 			continue
 		}
@@ -53,6 +49,7 @@
 		if err != nil {
 			t.Fatalf("Interfaces failed: %v", err)
 		}
+		var ifi *Interface
 		for _, x := range ift {
 			if x.Flags&tt.flags == tt.flags {
 				ifi = &x
@@ -80,6 +77,7 @@
 		if err != nil {
 			t.Fatalf("MulticastAddrs failed: %v", err)
 		}
+		var found bool
 		for _, ifma := range ifmat {
 			if ifma.(*IPAddr).IP.Equal(tt.gaddr) {
 				found = true