gpio: make analog pin support more versatile on the bbb

utils.go

@@ -0,0 +1,15 @@
+package embd
+
+import "path/filepath"
+
+// Inspiration: https://github.com/mrmorphic/hwio/blob/master/hwio.go#L451
+func findFirstMatchingFile(glob string) (string, error) {
+	matches, err := filepath.Glob(glob)
+	if err != nil {
+		return "", err
+	}
+	if len(matches) >= 1 {
+		return matches[0], nil
+	}
+	return "", nil
+}