The attached patch allows for a substring match for reader selection. Nowadays
there may be more than one reader and the plugin sequence of readers is since
the invention of USB somewhat random.
Thus it doesn't make sense to require an exact match on the PC/SC reader name as
this includes the current slot which, well, varies.
With the attached patch one can leave out the trailing slot information and
still get a reader match. Instead of strncmp() strstr() could be an even more
user friendly way but I wanted to stay as close to the current behaviour as
possible.

BTW and OT: Exclusive reader access is not so cute for modern tokens as these
usually do offer more than a single pgp applet - as for usability you don't want
to be a TJ (token jockey), one token should do. If users have to go through too
much hassle (multiple tokens, difficult configurations) they just won't use the
offered security measures.