staging: wilc1000: Remove useless function

GCC warns that 'wid' is unused in wilc_remove_key and it's correct; the
variable is only local. Get rid of the function (since it just returns
zero) and shuffle the remaining code into one if statement.

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>