iavf: Fix max_rate limiting

stable inclusion
from stable-v5.10.137
commit 692751f260996d6f48a7359e4dd2557e02192789
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=692751f260996d6f48a7359e4dd2557e02192789



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[ Upstream commit ec60d54c ]

Fix max_rate option in TC, check for proper quanta boundaries.
Check for minimum value provided and if it fits expected 50Mbps
quanta.

Without this patch, iavf could send settings for max_rate limiting
that would be accepted from by PF even the max_rate option is less
than expected 50Mbps quanta. It results in no rate limiting
on traffic as rate limiting will be floored to 0.

Example:
tc qdisc add dev $vf root mqprio num_tc 3 map 0 2 1 queues \
2@0 2@2 2@4 hw 1 mode channel shaper bw_rlimit \
max_rate 50Mbps 500Mbps 500Mbps

Should limit TC0 to circa 50 Mbps

tc qdisc add dev $vf root mqprio num_tc 3 map 0 2 1 queues \
2@0 2@2 2@4 hw 1 mode channel shaper bw_rlimit \
max_rate 0Mbps 100Kbit 500Mbps

Should return error

Fixes: d5b33d02 ("i40evf: add ndo_setup_tc callback to i40evf")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Jun Zhang <xuejun.zhang@intel.com>
Tested-by: Bharathi Sreenivas <bharathi.sreenivas@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>