staging: wilc1000: remove kmalloc wrapper

This patch calls kmalloc() directly. No need to wrap kmalloc().
All is not holding a spin lock or in interrupt context. So use GFP_KERNEL
flag for kmalloc.

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>