config/types/etcd: add support for v3.4 and v3.5 options

The structs were generated by parsing `etcd --help` output and
processing using a go program that I wrote. The program is available
here: https://gist.github.com/jepio/11f447c4f6270e2a23f66d7fa414f3a6.

Signed-off-by: Jeremi Piotrowski <[email protected]>

Author: jepio