src/runtime: Add missing defs for android/386.

Change-Id: I63bf6d2fdf41b49ff8783052d5d6c53b20e2f050
Reviewed-on: https://go-review.googlesource.com/13760Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>

src/runtime/defs_linux_386.go

@@ -90,6 +90,10 @@ const (
 	_EPOLL_CTL_ADD = 0x1
 	_EPOLL_CTL_DEL = 0x2
 	_EPOLL_CTL_MOD = 0x3
+
+	_AF_UNIX    = 0x1
+	_F_SETFL    = 0x4
+	_SOCK_DGRAM = 0x2
 )
 
 type fpreg struct {
@@ -218,3 +222,8 @@ type epollevent struct {
 	events uint32
 	data   [8]byte // to match amd64
 }
+
+type sockaddr_un struct {
+	family uint16
+	path   [108]byte
+}