Removed compiler warning of unused variable

src/AutoConnectUploadImpl.h

@@ -186,6 +186,9 @@ class AutoConnectUploadSD : public AutoConnectUploadHandler {
         sdVerify = (const char*)"UNKNOWN";
         break;
       }
+#endif
+#ifndef AC_DEBUG
+      AC_UNUSED(sdVerify);
 #endif
       AC_DBG("%s mounted\n", sdVerify);
       _file = _media->open(filename, oflag);