Staging: slicoss: add binary firmware to firmware directory

Adds the firmware to the firmware directory in ihex format so it can be
installed when doing make firmware_install.

Also update the firmware location in the driver code so it can locate
the files in the right place.

This should conclude the move to request_firmware().

Signed-off-by: Lior Dotan <liodot@gmail.com>
Cc: Christopher Harrer <charrer@alacritech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>