Which form is submitted? Internal or authorize?

This eliminates undefined form->property notices when user submitted internal form.

enrol/authorize/enrol.html

@@ -108,7 +108,7 @@ $usercountry = empty($form->cccountry) ? $USER->country : $form->cccountry;
   <?php if (!empty($this->ccerrors['cczip'])) { formerr($this->ccerrors['cczip']); } ?></td>
 </tr>
 </table>
-<input type="submit" value="<?php print_string("sendpaymentbutton", "enrol_authorize") ?>">
+<input type="submit" name="ccsubmit" value="<?php print_string("sendpaymentbutton", "enrol_authorize") ?>">
 </form>
 
 </div>

enrol/authorize/enrol.php

@@ -84,7 +84,7 @@ class enrolment_plugin extends enrolment_base
     function check_entry($form, $course) {
         if ((!empty($form->password)) || isguest() || $this->zero_cost($course)) {
             parent::check_entry($form, $course);
-        } elseif ($this->validate_enrol_form($form)) {
+        } elseif ((!empty($form->ccsubmit)) && $this->validate_enrol_form($form)) {
             $this->cc_submit($form, $course);
         }
     }