gendispatch: Avoid comparing signed and unsigned vars

The adminDispatchConnectListServers() function is generated by
our great perl script. However, it has a tiny flaw: if
adminConnectListServers() it calls fails, the control jumps onto
cleanup label where we try to free any list of servers built so
far. However, in the loop @i is unsigned (size_t) while @nresults
is signed (int). Currently, it does no harm because of the check
for @result being non-NULL. But if that ever changes in the
future, this bug will be hard to chase.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

src/rpc/gendispatch.pl

@@ -917,7 +917,7 @@ elsif ($mode eq "server") {
         print "    int rv = -1;\n";
 
         if ($modern_ret_as_list) {
-            print "    size_t i;\n";
+            print "    ssize_t i;\n";
         }
 
         foreach my $var (@vars_list) {