AppleHV enablement pass #2

* Use vfkit command line assembly
* Inject ignition file into guest using http over vsock
* Ready notification through use of vsock

[NO NEW TESTS NEEDED]

Signed-off-by: Brent Baude <bbaude@redhat.com>

vendor/github.com/twitchyliquid64/golang-asm/sys/supported.go

@@ -0,0 +1,116 @@
+// Copyright 2018 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.
+
+package sys
+
+// RaceDetectorSupported reports whether goos/goarch supports the race
+// detector. There is a copy of this function in cmd/dist/test.go.
+// Race detector only supports 48-bit VMA on arm64. But it will always
+// return true for arm64, because we don't have VMA size information during
+// the compile time.
+func RaceDetectorSupported(goos, goarch string) bool {
+	switch goos {
+	case "linux":
+		return goarch == "amd64" || goarch == "ppc64le" || goarch == "arm64"
+	case "darwin", "freebsd", "netbsd", "windows":
+		return goarch == "amd64"
+	default:
+		return false
+	}
+}
+
+// MSanSupported reports whether goos/goarch supports the memory
+// sanitizer option. There is a copy of this function in cmd/dist/test.go.
+func MSanSupported(goos, goarch string) bool {
+	switch goos {
+	case "linux":
+		return goarch == "amd64" || goarch == "arm64"
+	default:
+		return false
+	}
+}
+
+// MustLinkExternal reports whether goos/goarch requires external linking.
+func MustLinkExternal(goos, goarch string) bool {
+	switch goos {
+	case "android":
+		if goarch != "arm64" {
+			return true
+		}
+	case "darwin":
+		if goarch == "arm64" {
+			return true
+		}
+	}
+	return false
+}
+
+// BuildModeSupported reports whether goos/goarch supports the given build mode
+// using the given compiler.
+func BuildModeSupported(compiler, buildmode, goos, goarch string) bool {
+	if compiler == "gccgo" {
+		return true
+	}
+
+	platform := goos + "/" + goarch
+
+	switch buildmode {
+	case "archive":
+		return true
+
+	case "c-archive":
+		// TODO(bcmills): This seems dubious.
+		// Do we really support c-archive mode on js/wasm‽
+		return platform != "linux/ppc64"
+
+	case "c-shared":
+		switch platform {
+		case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/ppc64le", "linux/s390x",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"freebsd/amd64",
+			"darwin/amd64",
+			"windows/amd64", "windows/386":
+			return true
+		}
+		return false
+
+	case "default":
+		return true
+
+	case "exe":
+		return true
+
+	case "pie":
+		switch platform {
+		case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"freebsd/amd64",
+			"darwin/amd64",
+			"aix/ppc64",
+			"windows/386", "windows/amd64", "windows/arm":
+			return true
+		}
+		return false
+
+	case "shared":
+		switch platform {
+		case "linux/386", "linux/amd64", "linux/arm", "linux/arm64", "linux/ppc64le", "linux/s390x":
+			return true
+		}
+		return false
+
+	case "plugin":
+		switch platform {
+		case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/s390x", "linux/ppc64le",
+			"android/amd64", "android/arm", "android/arm64", "android/386",
+			"darwin/amd64",
+			"freebsd/amd64":
+			return true
+		}
+		return false
+
+	default:
+		return false
+	}
+}