fix golint for types/doc.go
fix golint for types/doc.go

Signed-off-by: cpanato <cc18de6eef6bcd724a531225b9b1eb27751129d8@gmail.com>
AmitKumarDas/maya,openebs/maya,prateekpandey14/maya,prateekpandey14/maya,AmitKumarDas/maya,openebs/maya,openebs/maya