[woa] dont abort if wait for net fails

When the 'wake on access' sequence starts, the first thing that is done is to wait for network connectivity (using CNetwork::HasInterfaceForIP()) for the server we need to wake.
If server is given by name, not ipaddress, a dns-lookup is made, but since server is offline that lookup may fail and so the HasInterfaceForIP() fails.
In this situation it is better to not give up (as today) but rather continue to issue a wol and see if the server comes up.

This scenario became clear int this post in this thread ; http://forum.xbmc.org/showthread.php?tid=203098&pid=1783818#pid1783818

If you hit cancel when this dialog is shown you cancel the step 'wait for network to connect' only, not necessarily the entire wakeup process. What we want to do is to support situation where server is specified by name and DNS fails to lookup ip. Without this fix those serves cant be woken