When ed25519 was introduced in commit 93c7b81b4ea1046bd2f65f4a510d5966786e8d3d,
the ed25519 case was added after the ecdsa case in src/pki.c. The ecdsa case seems to
have relied on falling through to report an error, when HAVE_ECC is not defined.
If HAVE_ECC is not defined, but ecdsa keys are used, with for example,
ssh_pki_import_pubkey_file, the code fallthroughs into the ed25519 case.
Signed-off-by: Juraj Vijtiuk <firstname.lastname@example.org>