linux-firmware: add Marvell SD8997 firmware image

WLAN (SDIO) firmware version: W16.68.1.p179
Bluetooth (SDIO) firmware version: W16.26.1.p179

Both WLAN and bluetooth are on SDIO interface.
The combo image can be downloaded either through WLAN or
Bluetooth.

Signed-off-by: Cathy Luo <cluo@marvell.com>
Signed-off-by: Ganapathi Bhat <gbhat@marvell.com>

WHENCE

@@ -765,6 +765,9 @@ Version: 16.68.1.p97
 File: mrvl/usbusb8997_combo_v4.bin
 Version: V16.68.1.p162
 
+File: mrvl/sdsd8997_combo_v4.bin
+Version: W16.68.1.p179
+
 Licence: Redistributable. See LICENCE.Marvell for details.  Originates from
 http://git.marvell.com/?p=mwifiex-firmware.git