staging: wilc1000: fix compilation warning for ARCH PowerPC

Fix below warning reported for PowerPC arch compilation

include/uapi/linux/byteorder/big_endian.h:95:37: warning: passing
argument 1 of '__swab32s' makes pointer from integer without a cast
[-Wint-conversion]

Fixes: 02211edc ("staging: wilc1000: fix endianness warnings reported by sparse")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>