scd: PC/SC reader selection by partial string match.
* scd/apdu.c (open_pcsc_reader_direct): Partial string match.
The card reader name by PC/SC service might include USB bus,
which varies (on some platform like GNU/Linux). Thus, it's
better to match partial string.
Original patch was submitted by anstein. I changed it to fallback to
the first reader if no match found.
Note that we need to change pcsc-wrapper.c in 2.0 backport.