gnupg21: Fix scdaemon for usb smartcards (#22891)

The use of smartcard functionality for yubikeys (and presumably other
usb smartcards) was broken in gnupg 2.1.18.  This has apparently already
been fixed in gnupg master, and debian backports the included patches
for 2.1.18.

See also:
https://bugs.gnupg.org/gnupg/issue2933
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=852702
https://github.com/NixOS/nixpkgs/pull/21991