scd: Migrate to new API of libusb 1.0.
* configure.ac (LIBUSB_CPPFLAGS): New. * scd/Makefile.am (AM_CPPFLAGS): Add LIBUSB_CPPFLAGS. * scd/ccid-driver.c: Use libusb 1.0 API.
Changes are straightforward, not use any new features.
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>