[bug#32358] Add pcscd service

[Arun Isaac]

> What problem does this pcsc-lite-bootstrap package solve?  It looks like
> you added pcsc-lite-bootstrap in order to avoid a cyclic dependency
> between ccid and pcsc-lite.  That seems fair, but is there any other
> reason that I'm missing?

No, there is no other reason. I only created pcsc-lite-bootstrap to
avoid a circular dependence between ccid and pcsc-lite.

> Do you know what the intent behind the --enable-usbdropdir option is in
> (1) the pcsc-lite configure script and (2) the ccid configure script?  I
> checked the README in the source for both of these packages, but I
> couldn't quite understand the intended use.  It wasn't clear to me if
> the usbdropdir directory is where the ccid/pcsc-lite expect to _find_
> drivers that the user makes available, or if this directory is where the
> packages will _install_ their own drivers (or both, perhaps).

I thought about this too. As far as I understood, the usbdropdir of the
ccid package is where it installs its drivers, and the usbdropdir of the
pcsc-lite package is where it expects to find drivers.

> If the usbdropdir is intended to house additional drivers that the user
> can "drop" in and use at runtime, then users of pcsc-lite/ccid might
> reasonably expect to be able to easily add additional drivers to the
> default configuration.  If that's the case, then we might want to think
> about how we can give a user the ability to configure additional
> drivers.  For example, if we gave the pcsc service configuration a field
> like "usbdropdir-drivers" (e.g. a list of packages or file-like
> objects), we could arrange for the union of those drivers to be placed
> into the usbdropdir for pcsc/ccid to use.

Good idea. I'll add a usb-drivers configuration field and send an
updated patchset.