[FAB-3968] BCCSP/pkcs11 code de-duplication

First pass, mostly all about rough code deletion.

There is a bit further code duplication on ECDSA side, but on
smaller scale, leaving for further patch sets.

The intention is to help with testing. The deleted code is a
copy of SW BCCSP. I either start copying even MORE changes
from SW BCCSP, or clean things up like this. I believe this
is preferable.

Change-Id: Ic17177c46359ee830e68d19d6545d51b7653e997
Signed-off-by: Volodymyr Paprotski <vpaprots@ca.ibm.com>