Cleanup the AES decryption code a bit
Cleanup the AES decryption code a bit

skaman/shairport,IronBeard/shairport,hendrikw82/shairport,IronBeard/shairport,albertz/shairport,narakai/shairport,hendrikw82/shairport,albertz/shairport,bowlofstew/shairport,narakai/shairport,hendrikw82/shairport,narakai/shairport,bowlofstew/shairport,bowlofstew/shairport,skaman/shairport,IronBeard/shairport