staging: wilc1000: fix return type of host_int_wait_msg_queue_idle

This patch changes return type of host_int_wait_msg_queue_idle from s32
to int. s32Error gets return value from wilc_mq_send that has return
type of int. It should be changed return type of
host_int_wait_msg_queue_idle by int as well as data type of s32Error.

Signed-off-by: Chaehyun Lim <chaehyun.lim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>