Description of ML2 Geneve type driver configuration options

Configuration option = Default value	Description
[ml2_type_geneve]
max_header_size = 50	(IntOpt) Geneve encapsulation header size is dynamic, this value is used to calculate the maximum MTU for the driver.this is the sum of the sizes of the outer ETH + IP + UDP + GENEVE header sizes
vni_ranges =	(ListOpt) Comma-separated list of <vni_min>:<vni_max> tuples enumerating ranges of Geneve VNI IDs that are available for tenant network allocation