staging: wilc1000: remove typedef from tstrHiddenNetworkInfo

This patch removes typedef from the struct tstrHiddenNetworkInfo with
related comments and renames it to hidden_net_info.

Signed-off-by: Leo Kim <leo.kim@atmel.com>
Signed-off-by: Tony Cho <tony.cho@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>