vendor golang.org/x/crypto using glide

This would help us build go-mtree on RHEL/CentOS and
distros where golang.org/x/crypto isn't provided or supported.

Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org>

vendor/golang.org/x/crypto/blake2b/blake2bAVX2_amd64.go

@@ -0,0 +1,43 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.7,amd64,!gccgo,!appengine
+
+package blake2b
+
+func init() {
+	useAVX2 = supportsAVX2()
+	useAVX = supportsAVX()
+	useSSE4 = supportsSSE4()
+}
+
+//go:noescape
+func supportsSSE4() bool
+
+//go:noescape
+func supportsAVX() bool
+
+//go:noescape
+func supportsAVX2() bool
+
+//go:noescape
+func hashBlocksAVX2(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte)
+
+//go:noescape
+func hashBlocksAVX(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte)
+
+//go:noescape
+func hashBlocksSSE4(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte)
+
+func hashBlocks(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte) {
+	if useAVX2 {
+		hashBlocksAVX2(h, c, flag, blocks)
+	} else if useAVX {
+		hashBlocksAVX(h, c, flag, blocks)
+	} else if useSSE4 {
+		hashBlocksSSE4(h, c, flag, blocks)
+	} else {
+		hashBlocksGeneric(h, c, flag, blocks)
+	}
+}