Staging: w35und: use gotos for error handling

The driver code uses do { } while (0) together with the break statement to
emulate gotos for error handling. Fix that up by using the goto statement
instead.

Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>