net/ice: fix overflow in maximum packet length config

net/ice: fix overflow in maximum packet length config

The len variable, used in the computation of max_pkt_len could overflow,
if used to store the result of the following computation:

ICE_SUPPORT_CHAIN_NUM * rxq->rx_buf_len

Since, we could define the mbuf size to have a large value (i.e 13312),
and ICE_SUPPORT_CHAIN_NUM is defined as 5, the computation mentioned
above could potentially result in a value which might be bigger than
MAX_USHORT.

The result will be that Jumbo Frames will not work properly

Fixes: 1b009275e2c8 ("net/ice: add Rx queue init in DCF")
Cc: stable@dpdk.org
Signed-off-by: Tudor Cornea <tudor.cornea@keysight.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>