staging: wilc1000: remove platform version checks

For code that is integrated into mainline Linux, checks for
the OS platform make no sense, because we know that we
are on Linux.

This removes all checks and the associated dead code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>