RijndaelTest: Fix broken test for AES-192/Rijndael(192,128)

This test only failed due to use of wrong block size.
Minor speedup for PCFBMode

Simplify condition inside main loop, move special cases out of
main loop.
Improved speed by 2-3%.
Also s/protected/private/ leftover.
Fix build due to applying patches in a different order to Eleriseth
Rijndael_Algorithm: speed-up makeKey by 15-18%

By replacing / and % with >>> and & for pow-of-2 blockSize.
Drop support for blockSize 192 bits.
Complete previous commit - do not support 192-bit block size for Rijndael.