mwifiex: add support for SD8786 sdio

	modified:   drivers/net/wireless/mwifiex/Kconfig
	- notate additional chipset
	modified:   drivers/net/wireless/mwifiex/sdio.c
	- add definition of id (0x9116)
	- add to switch for firmware load
	- add MODULE_FIRMWARE
	modified:   drivers/net/wireless/mwifiex/sdio.h
	- add definition of default firmware name

Signed-off-by: Jason Plum <max@warheads.net>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>