staging: wilc1000: remove wilc_debug_func of hif_init

This patch removes wilc_debug_func of hif_init and remove it's related
functions as well because it is not used anymore.

Signed-off-by: Glen Lee <glen.lee@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>