brcmfmac: add 43242 device id for LG dongle

Got a hint on IRC that a 43242 dongle for LG smart TV's works with
brcmfmac:

> Hello - I recently got a LG AN-WF500 wireless dongle for LG's SmartTVs.
> From the information I gathered it uses a Broadcom chipset BCM43242.
> The device should have been supported by brcmfmac kernel driver if it used
> USB IDs 0a5c:bd1f.
> My device however identifies itself as "ID 043e:3101 LG Electronics USA, Inc.".
> I then tried adding the USB ID to the driver with
> "echo "043e 3101" > /sys/bus/usb/drivers/brcmfmac/new_id" and it just works.
> The kernel provides the following information.
> [15958.851291] usb 3-1.1.3: new high-speed USB device number 53 using ehci-pci
> [15958.946723] usb 3-1.1.3: New USB device found, idVendor=043e, idProduct=3101
> [15958.946728] usb 3-1.1.3: New USB device strings: Mfr=1, Product=4, SerialNumber=3
> [15958.946731] usb 3-1.1.3: Product: Composite Wireless Adapter
> [15958.946733] usb 3-1.1.3: Manufacturer: Broadcom
> [15958.946735] usb 3-1.1.3: SerialNumber: 28458

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>