internal/rosa: add arm64 strings

This enables building on arm64.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/llvm.go

@@ -208,6 +208,8 @@ func (t Toolchain) newLLVM() (musl, compilerRT, runtimes, clang pkg.Artifact) {
 	switch runtime.GOARCH {
 	case "386", "amd64":
 		target = "X86"
+	case "arm64":
+		target = "AArch64"
 
 	default:
 		panic("unsupported target " + runtime.GOARCH)

internal/rosa/rosa.go

@@ -49,6 +49,8 @@ func linuxArch() string {
 	switch runtime.GOARCH {
 	case "amd64":
 		return "x86_64"
+	case "arm64":
+		return "aarch64"
 
 	default:
 		panic("unsupported target " + runtime.GOARCH)