staging: wilc1000: remove function linux_wlan_rxq_task

linux_wlan_rxq_task is not used in the driver. Just remove it.

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