HID: playstation: fix free of uninialized pointer for DS4 in Bluetooth.

The 'buf' variable is only used in the USB (if-path) and not in the Bluetooth
else-path. Since it is not set to NULL. this results in freeing an uninitialized
pointer. Since the else code-path doesn't need buf, just return 0.

Fixes: 2d77474a23 ("HID: playstation: add DualShock4 bluetooth support.")
Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20221213044935.1775499-2-roderick.colenbrander@sony.com

drivers/hid/Kconfig

@@ -897,7 +897,7 @@ config HID_PLAYSTATION
 	select CRC32
 	select POWER_SUPPLY
 	help
-	  Provides support for Sony PS5 controllers including support for
+	  Provides support for Sony PS4/PS5 controllers including support for
 	  its special functionalities e.g. touchpad, lights and motion
 	  sensors.
 

drivers/hid/hid-playstation.c

@@ -1916,7 +1916,7 @@ static int dualshock4_get_mac_address(struct dualshock4 *ds4)
 		if (ret != sizeof(ds4->base.mac_address))
 			return -EINVAL;
 
-		ret = 0;
+		return 0;
 	}
 
 err_free: