mkosi: add dependency on libgcrypt20 for Debian

systemctl: error while loading shared libraries: libgcrypt.so.20: cannot open shared object file: No such file or directory

Author: bluca

mkosi.default.d/debian/10-mkosi.debian

@@ -19,6 +19,7 @@ Packages=
         isc-dhcp-server
         libbpf1
         libfido2-1
+        libgcrypt20
         libglib2.0-0
         libgnutls30
         libidn2-0