Use G_ELI_IVKEYLEN as the size of IV in the user test code.

[jhb]

Summary

IVs are not the size of keys as a general case. Most often they are
the size of a single block.

Sponsored by: The FreeBSD Foundation

[imp]

Do you need a kassert G_ELI_IVKEYLEN >= keysize?

[jhb]

In D33885#766236, @imp wrote:

Do you need a kassert G_ELI_IVKEYLEN >= keysize?

No, the entire point is that IV sizes have no relation to key sizes. For the ciphers involved in fact, the key sizes are generally larger than the IVs (e.g. 8 byte IV for AES-XTS vs a 256/512 bit key).