scd: Internal CCID driver: More fix for SPR532.
* scd/ccid-driver.c (bulk_in): Handle the case of missing intr_cb.
Backport master commit of:
920f258eb6018ecec1d63bad6a0fb0772f72affa
- GnuPG-bug-id: T5065
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>