Since version 2.3, GnuPG no longer falls back to other access methods if
its built-in CCID driver fails to access smartcards, including yubikeys.
The built-in CCID driver fails on macOS.
The upstream developers recommend disabling CCID support in this case:
If it works and the distribution doesn't offer appropriate USB
configuration, I think that it's good for the distribution to use
--disable-ccid-driver for building GnuPG.
Cite: https://dev.gnupg.org/T5415
See also: https://dev.gnupg.org/T5409Fixes#155629
pcsclite pulls in a lot of dependencies, including spidermonkey, which is
nearly or completely impossible to build on 32-bit architectures. PC/SC support
is not commonly used, so provide a flag to allow users to disable it and
significantly reduce the closure size.
