dpaa2-eth: fix draining of S/G cache

On link down, the draining of the S/G cache should be done on all
_possible_ CPUs not just the ones that are online in that moment.
Fix this by changing the iterator.

Fixes: d70446ee ("dpaa2-eth: send a scatter-gather FD instead of realloc-ing")
Reported-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NIoana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c

@@ -1261,7 +1261,7 @@ static void dpaa2_eth_sgt_cache_drain(struct dpaa2_eth_priv *priv)
 	u16 count;
 	int k, i;
 
-	for_each_online_cpu(k) {
+	for_each_possible_cpu(k) {
 		sgt_cache = per_cpu_ptr(priv->sgt_cache, k);
 		count = sgt_cache->count;