util: remove test code accidentally committed to virFirewallDZoneExists

Just before pushing the series containing commit 3bba4825 I had added
a "return true" to the top of virFirewallDZoneExists() to measure the
impact of calling that function once per network during startup. I
found that the effect was minimal, but forgot to remove the "return
true" before pushing. This unfortunately causes a failure to start
networks on systems that have a firewalld version that doesn't support
our libvirt zone file (i.e. pretty much everyone).

This patch removes the unintended line.
Signed-off-by: NLaine Stump <laine@laine.org>

src/util/virfirewalld.c

@@ -235,8 +235,6 @@ virFirewallDZoneExists(const char *match)
     char **zones = NULL;
     bool result = false;
 
-    return true;
-
     if (virFirewallDGetZones(&zones, &nzones) < 0)
         goto cleanup;