a trivial bug fix: -a wasn't recognized.

this is very trivial so I'll skip explicit review.


git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@2470 e5f2f494-b856-4b98-b285-d166d9295462

src/bin/auth/main.cc

@@ -98,7 +98,7 @@ main(int argc, char* argv[]) {
     const char* address = NULL;
     bool use_ipv4 = true, use_ipv6 = true, cache = true;
 
-    while ((ch = getopt(argc, argv, "46np:v")) != -1) {
+    while ((ch = getopt(argc, argv, "46a:np:v")) != -1) {
         switch (ch) {
         case '4':
             // Note that -4 means "ipv4 only", we need to set "use_ipv6" here,