patch for compile errors when KRB5_DNS_LOOKUP is false on 1.9.1

[Chris Hecker]

   I'm getting a compile error on 1.9.1 if KRB5_DNS_LOOKUP is false in
   locate_kdc.c because dns_locate_server calls locate_srv_dns_1, which
   is in an ifdef block.  The calls to dns_locate_server are ifdefed, but
   the function itself isn't.  This is true in trunk as well.
   Also, MAX_DNS_NAMELEN is not defined in k5-int.h if KRB5_DNS_LOOKUP is
   off, which makes kdc_util.c not compile.
   kdc_util.c:2502: error: `MAX_DNS_NAMELEN' undeclared (first use in
   this function)
   The obvious patch is below.
   Chris
   diff -ur krb5-1.9.1.orig/src/include/k5-int.h
   krb5-1.9.1/src/include/k5-int.h
   --- krb5-1.9.1.orig/src/include/k5-int.h        2010-12-02
   18:05:44.000000000 -0600
   +++ krb5-1.9.1/src/include/k5-int.h     2011-07-23 23:48:08.000000000
   -0500
   @@ -2258,10 +2258,10 @@
        unsigned short port;
        char *host;
    };
   -#ifdef KRB5_DNS_LOOKUP
   -
    #define MAX_DNS_NAMELEN (15*(MAXHOSTNAMELEN + 1)+1)
   +#ifdef KRB5_DNS_LOOKUP
   +
    krb5_error_code
    krb5int_make_srv_query_realm(const krb5_data *realm,
                                 const char *service,
   diff -ur krb5-1.9.1.orig/src/lib/krb5/os/locate_kdc.c
   krb5-1.9.1/src/lib/krb5/os/locate_kdc.c
   --- krb5-1.9.1.orig/src/lib/krb5/os/locate_kdc.c        2010-05-27
   17:25:51.000000000 -0500
   +++ krb5-1.9.1/src/lib/krb5/os/locate_kdc.c     2011-07-23
   23:29:20.000000000 -0500
   @@ -693,6 +693,7 @@
                                 dflport1, dflport2, family);
    }
   +#ifdef KRB5_DNS_LOOKUP
    static krb5_error_code
    dns_locate_server (krb5_context context, const krb5_data *realm,
                       struct addrlist *addrlist,
   @@ -738,6 +739,7 @@
        }
        return code;
    }
   +#endif
    /*
     * Wrapper function for the various backends