crypto: octeontx2 - uninitialized variable in kvf_limits_store()

If kstrtoint() fails then "lfs_num" is uninitialized and the warning
doesn't make any sense.  Just delete it.

Fixes: 8ec8015a ("crypto: octeontx2 - add support to process the crypto request")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>