Remove the obsolete bluetooth code

Also update the shortcut:
1. Change the name to "Devices"
2. Change it point to "Connected device" page

Bug: 74806595
Fixes: 69926683
Test: robo test still pass

Change-Id: Ic57756fc955dc622cc22d0be64f02b5ae07a2915

src/com/android/settings/bluetooth/DevicePickerActivity.java

@@ -23,7 +23,7 @@ import com.android.settings.R;
 
 /**
  * Activity for Bluetooth device picker dialog. The device picker logic
- * is implemented in the {@link BluetoothSettings} fragment.
+ * is implemented in the {@link BluetoothPairingDetail} fragment.
  */
 public final class DevicePickerActivity extends Activity {