Revert "remove krb5 authorize_localname impl, there's no krb5_kuserok"

This reverts commit 4b92552c1e.

lib/gssapi/krb5/authorize_localname.c

@@ -38,7 +38,6 @@ _gsskrb5_authorize_localname(OM_uint32 *minor_status,
                              gss_const_buffer_t user_name,
                              gss_const_OID user_name_type)
 {
-#if 0
     krb5_context context;
     krb5_principal princ = (krb5_principal)input_name;
     char *user;
@@ -64,8 +63,4 @@ _gsskrb5_authorize_localname(OM_uint32 *minor_status,
     free(user);
 
     return user_ok ? GSS_S_COMPLETE : GSS_S_UNAUTHORIZED;
-#else
-    *minor_status = 0;
-    return GSS_S_UNAUTHORIZED;
-#endif
 }