crypto: marvell/octeontx - prevent integer overflows

The "code_length" value comes from the firmware file.  If your firmware
is untrusted realistically there is probably very little you can do to
protect yourself.  Still we try to limit the damage as much as possible.
Also Smatch marks any data read from the filesystem as untrusted and
prints warnings if it not capped correctly.

The "code_length * 2" can overflow.  The round_up(ucode_size, 16) +
sizeof() expression can overflow too.  Prevent these overflows.

Fixes: d9110b0b ("crypto: marvell - add support for OCTEON TX CPT engine")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>