libaes_siv for OpenSSL 3

[Hal Murray]

Your code builds and works on all my Openssl 3.0 testing with NTPsec on Linux, 
FreeBSD and NetBSD.

aes_siv.c gets a handful for warnings from CMAC being deprecated.

Is it OK if I add this line to our copy to suppress those warnings?
  #define OPENSSL_SUPPRESS_DEPRECATED 1
Or would you prefer to do it to your master copy?  ...

---------

We have the same problem in our shared key code.  Fixing it hasn't gotten to 
the top of my list yet, but it's close.  There are several clean ways to do 
the CMAC work in 3.0.  I forget which is faster.  It's in one of my attic 
hacks.  It won't take long to refresh my
memory but I probably won't get to it until after the release.




-- 
These are my opinions.  I hate spam.