Revert "update to use containerd seccomp package"

This reverts commit 4f8e065faf055d3f0463a92622297ca3afac07f4.

vendor/github.com/docker/distribution/registry/handlers/basicauth.go

@@ -0,0 +1,11 @@
+// +build go1.4
+
+package handlers
+
+import (
+	"net/http"
+)
+
+func basicAuth(r *http.Request) (username, password string, ok bool) {
+	return r.BasicAuth()
+}