ssh: add two missing state names

The list of state names (used in debug builds) was out of sync in
relation to the list of states (used in all builds).

I now added an assert to make sure the sizes of the two lists match, to
aid in detecting this mistake better in the future.

Regression since c92d2e14, shipped in 7.58.0.

Reported-by: Somnath Kundu

Fixes #2312
Closes #2313