staging: wilc1000: remove WILC_OSW_INTERFACE_VER define

This patch removes WILC_OSW_INTERFACE_VER define that is not used
anywhere.

Signed-off-by: Chaehyun Lim <chaehyun.lim@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>