Add type to allow ECDSA keys

Some tempest tests will fail under FIPS because they are trying to
ssh to a cirrus instance that has a version of dropbear that does
not support signatures other than using SHA-1 for RSA keys. This
is not allowed under FIPS.  The workaround until cirros is updated
is to use ECDSA keys.  This patch allows the key type to be
specified.

Depends-On: https://review.opendev.org/c/openstack/tempest/+/807465
Change-Id: I34ac429ab5442cef056ee8b63fcb2ba41e8b9b27
2 files changed