dpaa2-eth: fix condition for number of buffer acquire retries

dpaa2-eth: fix condition for number of buffer acquire retries

[ Upstream commit 0e5ad75b02d9341eb9ca22627247f9a02cc20d6f ]

We should keep retrying to acquire buffers through the software portals
as long as the function returns -EBUSY and the number of retries is
__below__ DPAA2_ETH_SWP_BUSY_RETRIES.

Fixes: ef17bd7cc0c8 ("dpaa2-eth: Avoid unbounded while loops")
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>