gpg,sm: Simplify keyserver spec parsing.

* common/keyserver.h: Remove.
* sm/gpgsm.h (struct keyserver_spec): Remove.
(opt): Change keyserver to a strlist_t.
* sm/gpgsm.c (keyserver_list_free): Remove.
(parse_keyserver_line): Remove.
(main): Store keyserver in an strlist.
* sm/call-dirmngr.c (prepare_dirmngr): Adjust for the strlist.  Avoid
an ambiguity in dirmngr by adding a prefix if needed.

* g10/options.h (struct keyserver_spec): Move definition from
keyserver.h to here.  Remove most fields.
* g10/keyserver.c (free_keyserver_spec): Adjust.
(cmp_keyserver_spec): Adjust.
(parse_keyserver_uri): Simplify.
(keyidlist): Remove fakev3 arg which does not make any sense because
we don't even support v3 keys.
--

We now rely on the dirmngr to parse the keyserver specs.  Thus a bad
specification will not be caught immediately.  However, even before
that dirmngr had stricter tests.

Signed-off-by: Werner Koch <wk@gnupg.org>

doc/gpg.texi

@@ -1929,10 +1929,7 @@ keys on. The format of the @var{name} is a URI:
 "hkp"/"hkps" for the HTTP (or compatible) keyservers or "ldap"/"ldaps"
 for the LDAP keyservers.  Note that your particular installation of
 GnuPG may have other keyserver types available as well. Keyserver
-schemes are case-insensitive. After the keyserver name, optional
-keyserver configuration options may be provided. These are the same as
-the global @option{--keyserver-options} from below, but apply only to
-this particular keyserver.
+schemes are case-insensitive.
 
 Most keyservers synchronize with each other, so there is generally no
 need to send keys to more than one server. The keyserver