crypto: marvell/octeontx - remove redundant initialization of variable c_size

Variable c_size is being initialized with a value that is never read, it
is being re-assigned with a different value later on. The initialization
is redundant and can be removed.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>