imxtools/sbtools: switch AES implementation to Crypto++

Instead of having our own copy of the AES code, use a good library to do that.
Crypto++ is well-maintained, supports a lot of ciphers, works on many OSes, and
is optimized for many architectures.

Change-Id: I7d7d24b47993206d7338c5f9bac8bbdd3915a667
5 files changed