LPS-49008: Javascript bug when you only have "general" authentication form

Related to LPP-12527.

The bug happens because the method of saveLdap() in undefined when calling the method of saveCompany() on clicking save button. This method is defined in the ldap.jsp, but  the jsp is not called because of setting "company.settings.form.authentication=general" in portal-ext.properties.

So. the solution is check the method whether it is defined when calling it.