qa/507: use -h localhost instead of -h $qahost

In CI, for some containers, the FQDN we get for the local
hostname is a very long name like:
fv-az1984-647.ddddlmzljshefgqgcv3uanxwgh.cx.internal.cloudapp.net
that fails a DNS lookup or maps to a different interface IP addr
and we can't connect to pmcd there.

For the purposes of this test -h localhost works just as well.

qa/507

@@ -117,8 +117,8 @@ do
     echo "=== no args ===" >>$seq.full
     pcp 2>&1 | tee -a $seq.full | _filter > $tmp.noargs
     statusna=$?
-    echo "=== -h $qahost args ===" >>$seq.full
-    pcp -h $qahost 2>&1 | tee -a $seq.full | _filter > $tmp.local
+    echo "=== -h localhost args ===" >>$seq.full
+    pcp -h localhost 2>&1 | tee -a $seq.full | _filter > $tmp.local
     statusll=$?
     export PMCD_HOST=$qahost
     echo "=== \$PMCD_HOST=$PMCD_HOST args ===" >>$seq.full