Migrate to containerd v1.7.0 and update dependencies

* Updates containerd to v1.7.0 and new binary for 32-bit
Arm OSes.
* Updates Go dependencies - openfaas and external

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

vendor/github.com/containerd/continuity/fs/copy_irregular_freebsd.go

@@ -0,0 +1,36 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package fs
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+)
+
+// copyIrregular covers devices, pipes, and sockets
+func copyIrregular(dst string, fi os.FileInfo) error {
+	st, ok := fi.Sys().(*syscall.Stat_t) // not *unix.Stat_t
+	if !ok {
+		return fmt.Errorf("unsupported stat type: %s: %v", dst, fi.Mode())
+	}
+	var rDev uint64 // uint64 on FreeBSD, int on other unixen
+	if fi.Mode()&os.ModeDevice == os.ModeDevice {
+		rDev = st.Rdev
+	}
+	return syscall.Mknod(dst, uint32(st.Mode), rDev)
+}