added arm detector

orangefork/orangefork.go

@@ -0,0 +1,8 @@
+package orangefork
+
+func Foo() string {
+	if isArm {
+		return "is arm"
+	}
+	return "is not arm"
+}

orangefork/orangefork_arm64.go

@@ -0,0 +1,6 @@
+//go:build arm64
+// +build arm64
+
+package orangefork
+
+const isArm = true

orangefork/orangefork_other.go

@@ -0,0 +1,6 @@
+//go:build !arm && !arm64
+// +build !arm,!arm64
+
+package orangefork
+
+const isArm = false

orangefork/orangepi_arm.go

@@ -0,0 +1 @@
+package orangefork