Make friver optional in drof.streams.xml

[anton-seaice]

For panant models, we need a method to make friver optional when generating drof.streams.xml

om3-scripts/data_stream_xml_generation/generate_xml_drof_jra55.py

Lines 57 to 61 in 0e71249

	# Define the stream info names and corresponding var names
	stream_info_data = [
	("JRA55do.FRIVER", "friver", "Forr_rofl"),
	("JRA55do.LICALVF", "licalvf", "Forr_rofi"),
	]

https://github.com/ACCESS-NRI/access-om3-configs/pull/1078/changes#r3455988988