syscall: Set SizeofSockaddrAny to the value the go distribution uses

In particular this means that the names Getsockname returns are not
truncated to 26 characters.

Fixes issue 6829

https://codereview.appspot.com/31840043/

From-SVN: r205368

libgo/go/syscall/socket.go

@@ -25,7 +25,7 @@ type RawSockaddrAny struct {
 	Pad  [96]int8
 }
 
-const SizeofSockaddrAny = 0x1c
+const SizeofSockaddrAny = 0x6c
 
 type SockaddrInet4 struct {
 	Port int