crypto: inside-secure - remove useless check

When sending an ahash request, the code checks for the extra variable
not to be 0. This check is useless as the extra variable can't be 0 at
this point (it is checked on the line just before).

This patch does not modify the driver behaviour in any way.

Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>