Fix the sanity check on number of query/verify sources (RhBug:691930)

- Prior to commit 2e672f3fae, the
  callback would get called twice for every option so the expected
  number of query/verify sources was doubled. Now the numbers
  match with reality, adjust the check.

rpmqv.c

@@ -117,7 +117,7 @@ int main(int argc, char *argv[])
     }
 
     if (qva->qva_sourceCount) {
-	if (qva->qva_sourceCount > 2)
+	if (qva->qva_sourceCount > 1)
 	    argerror(_("one type of query/verify may be performed at a "
 			"time"));
     }