Allow for crypto instances to be configured with symmetric crypto rings
that belong to a bank that is different from the one where asymmetric
crypto rings are located.

This is to allow for devices with banks made of a single ring pair.
In these, crypto instances will be composed of two separate banks.

Changed string literals are not exposed to the user space.
Signed-off-by: NGiovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: NWojciech Ziemba <wojciech.ziemba@intel.com>
Reviewed-by: NFiona Trahe <fiona.trahe@intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>