crypto: inside-secure - Minor optimization recognizing CTR is always AES

Moved counter mode handling code in front as it doesn't depend on the
rest of the code to be executed, it can just do its thing and exit.

Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>