Add a helper function AmlCodeGenEndTag() to generate AML Resource Data EndTag. The EndTag resource data is automatically generated by the ASL compiler at the end of a list of resource data elements. Therefore, an equivalent function is not present in ASL. However, AmlCodeGenEndTag() is useful when generating AML code for the ResourceTemplate() macro. Reviewed-by: Sami Mujawar <sami.mujawar@arm.com> Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>