PJ: simplify link recipes

DOSBox does not implement "COPY x+y x" correctly, where x appears as
both source and destination.  This was used in some make rules to
concatenate several files into a single response file for wlib.

There seems to be no reason not to use multiple response file arguments
to wlib instead.  Perhaps this was not supported in earlier versions?
PJ: use wlib /n switch

Use the wlib /n switch to create new .lib files, rather than deleting
the targets first.  This avoids warning messages from both del and
wlib about non-existent files.

Perhaps the /n switch did not exist in previous versions?
PJ: ignore code for the hardware lock
PJ: delete calls to donothin command

How does it differ from an empty makefile recipe?