Cannot login into emulated smartcard with OpenSC because it expects external PIN pad.

[Andrei Borzenkov]

USB card reader emulated by QEMU announces presence of PIN pad. OpenSC
will not request PIN from user in this case and assumes PIN is being
entered off-band on external device. Unfortunately QEMU does not seem to
offer PIN entry and access to card always fails.

Changing device to not announce non-existing capability fixes it and
allows to use OpenSC framework with emulated card.

--- a/hw/usb/dev-smartcard-reader.c
+++ b/hw/usb/dev-smartcard-reader.c
@@ -398,7 +398,7 @@ static const uint8_t qemu_ccid_descriptor[] = {
                      * u16 wLcdLayout; XXYY Number of lines (XX) and
chars per
                      * line for LCD display used for PIN entry. 0000 -
no LCD
                      */
-        0x01,       /*
+        0x00,       /*
                      * u8  bPINSupport; 01h PIN Verification,
                      *                  02h PIN Modification
                      */