staging: wilc1000: remove goto from mac_open

This patch removes goto from mac_open function. If address is invalid, goto
handles deinit process and return result.
So, just call deinit process and return the error value directly instead of
goto statement.

Signed-off-by: Leo Kim <leo.kim@atmel.com>
Signed-off-by: Glen Lee <glen.lee@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>