add vendor data

vendor/golang.org/x/net/ipv4/zsys_darwin.go

@@ -0,0 +1,59 @@
+// Code generated by cmd/cgo -godefs; DO NOT EDIT.
+// cgo -godefs defs_darwin.go
+
+package ipv4
+
+const (
+	sizeofSockaddrStorage = 0x80
+	sizeofSockaddrInet    = 0x10
+	sizeofInetPktinfo     = 0xc
+
+	sizeofIPMreq         = 0x8
+	sizeofIPMreqSource   = 0xc
+	sizeofGroupReq       = 0x84
+	sizeofGroupSourceReq = 0x104
+)
+
+type sockaddrStorage struct {
+	Len         uint8
+	Family      uint8
+	X__ss_pad1  [6]int8
+	X__ss_align int64
+	X__ss_pad2  [112]int8
+}
+
+type sockaddrInet struct {
+	Len    uint8
+	Family uint8
+	Port   uint16
+	Addr   [4]byte /* in_addr */
+	Zero   [8]int8
+}
+
+type inetPktinfo struct {
+	Ifindex  uint32
+	Spec_dst [4]byte /* in_addr */
+	Addr     [4]byte /* in_addr */
+}
+
+type ipMreq struct {
+	Multiaddr [4]byte /* in_addr */
+	Interface [4]byte /* in_addr */
+}
+
+type ipMreqSource struct {
+	Multiaddr  [4]byte /* in_addr */
+	Sourceaddr [4]byte /* in_addr */
+	Interface  [4]byte /* in_addr */
+}
+
+type groupReq struct {
+	Interface uint32
+	Pad_cgo_0 [128]byte
+}
+
+type groupSourceReq struct {
+	Interface uint32
+	Pad_cgo_0 [128]byte
+	Pad_cgo_1 [128]byte
+}