syscall: regenerate syscall/z* files for linux/386, linux/amd64

DISTRIB_DESCRIPTION="Ubuntu 10.04 LTS"

Use <sys/user.h> instead of <linux/user.h>
See http://gcc.gnu.org/ml/gcc-patches/2009-11/msg00834.html for more details.

R=imkrasin, rsc
CC=golang-dev
https://golang.org/cl/1957041

src/pkg/syscall/syscall_linux.go

@@ -369,7 +369,7 @@ func Socket(domain, typ, proto int) (fd, errno int) {
 }
 
 func Socketpair(domain, typ, proto int) (fd [2]int, errno int) {
-	fd, errno = socketpair(domain, typ, proto)
+	errno = socketpair(domain, typ, proto, &fd)
 	return
 }