Call temp mounts and unmount in containerd server

Fixes #2004

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

mount/temp_unsupported.go

@@ -0,0 +1,13 @@
+// +build windows
+
+package mount
+
+// SetTempMountLocation sets the temporary mount location
+func SetTempMountLocation(root string) error {
+	return nil
+}
+
+// CleanupTempMounts all temp mounts and remove the directories
+func CleanupTempMounts(flags int) error {
+	return nil
+}