staging: wilc1000: remove typedef of struct Pending_Acks_info_t

This patch remove typedef of struct Pending_Acks_info_t.
And, rename the Pending_Acks_info_t to pending_acks_info.

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