DNS: don't count search-path miss as a retry

Currently a miss on a search-path entry is counted as a retry.  This means that
users with more than (num_nameservers * retries) entries in their search path
list fail before trying all search paths.  Concretely, a single nameserver with
4 search paths will never try the 4th search because the default retry is 3.

The code doesn't currently retry a given nameserver in case of an error, so
retries is sort of meaningless (though there are some comments indicating it
might come).  This change only treats total failure of a nameserver (try next
server) as a retry.

Signed-off-by: Tim Hockin <thockin@google.com>

libc/inet/resolv.c

@@ -1320,7 +1320,6 @@ int __dns_lookup(const char *name,
 				local_ns_num = last_ns_num;
 			retries_left = __nameservers * __resolv_attempts;
 		}
-		retries_left--;
 		if (local_ns_num >= __nameservers)
 			local_ns_num = 0;
 		local_id++;
@@ -1572,6 +1571,7 @@ int __dns_lookup(const char *name,
 
  try_next_server:
 		/* Try next nameserver */
+		retries_left--;
 		local_ns_num++;
 		variant = -1;
 	} while (retries_left > 0);