dirmngr: Handle missing nsswitch.conf.
* dirmngr/dns-stuff.c (libdns_init): Fallback to files,dns.
ChangeLog entry by wk.
This fixed the problem:
Short version: macOS doesn't include /etc/nsswitch.conf and GnuPG's dirmngr is hard-erroring when that file is missing, such that no DNS operations succeed and --recv-key returns ENOENT type errors to the caller.
- Signed-off-by: Werner Koch <firstname.lastname@example.org>