* configure.ac: Don't check for usb_create_match or
use_get_string_simple anymore.
* g10.c (list_config): New config option ccid-reader-id.
(gpgconf_list): Add "reader-port".
* apdu.c (open_ccid_reader): New arg PORTSTR.  Pass it to
ccid_open_reader.
(apdu_open_reader): Pass portstr to open_ccid_reader.
* ccid-driver.c (ccid_get_reader_list): New.
(ccid_open_reader): Changed API to take a string for the reader.
Removed al the cruft for the libusb development vesion which seems
not to be maintained anymore and there are no packages anyway.
The stable library works just fine.
(struct ccid_reader_id_s): Deleted and replaced everywhere by a
simple string.
(usb_get_string_simple): Removed.
(bulk_in): Do valgrind hack here and not just everywhere.