* gpgkeys_ldap.c (fail_all): New function to unwind a keylist and error
each item. (main): Call fail_all from here, as needed.  Also add a
NO_MEMORY error in an appropriate place and fix error return code.
(ldap_err_to_gpg_err): Add KEYSERVER_UNREACHABLE.
* gpgkeys_hkp.c (fail_all): New function to unwind a keylist and error
each item. (main): Call fail_all from here.  Also add a NO_MEMORY error in
an appropriate place. (get_key): Use new UNREACHABLE error for network
errors.