net: dsa: qca8k: fix warning in LAG feature

Fix warning reported by bot.
Make sure hash is init to 0 and fix wrong logic for hash_type in
qca8k_lag_can_offload.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: def97530 ("net: dsa: qca8k: add LAG support")
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20211123154446.31019-1-ansuelsmth@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>