staging: vt6656: don't leak 'param' in vt6656_hostap_ioctl() when returning -EOPNOTSUPP

Don't return -EOPNOTSUPP directly in switch case's since it'll leak
the memory allocated to 'param' when that variable goes out of scope
without having been assigned to anything.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>