net/wireless/wl18xx: Add missing MODULE_FIRMWARE

Fixes the output of 'modinfo --field firmware'.
Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ti/wl18xx/main.c

@@ -2115,3 +2115,4 @@ MODULE_PARM_DESC(num_rx_desc_param,
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
 MODULE_FIRMWARE(WL18XX_FW_NAME);
+MODULE_FIRMWARE(WL18XX_CONF_FILE_NAME);