Put a bit of order in the src directory, group and name things appropriately

src/platform/rp2040/main-rp2040.cpp

@@ -0,0 +1,30 @@
+#include "configuration.h"
+#include <stdio.h>
+#include <pico/unique_id.h>
+
+void setBluetoothEnable(bool on)
+{
+    // not needed
+}
+
+void cpuDeepSleep(uint64_t msecs)
+{
+    // not needed
+}
+
+void updateBatteryLevel(uint8_t level)
+{
+    // not needed
+}
+
+void getMacAddr(uint8_t *dmac)
+{
+    pico_unique_board_id_t src;
+    pico_get_unique_board_id(&src);
+    dmac[5] = src.id[0];
+    dmac[4] = src.id[1];
+    dmac[3] = src.id[2];
+    dmac[2] = src.id[3];
+    dmac[1] = src.id[4];
+    dmac[0] = src.id[5];
+}