crypto: nx - Removing CTR mode from NX driver

CTR hardware implementation does not match with kernel spec causing a counter bug
where just low 8 bytes are used for counter, when should be all 16bytes.

Since we already have other counter modes working according with specs
not worth to keep CTR itself on NX.

Signed-off-by: Leonidas S. Barbosa <leosilva@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>