[hns3-0114]net: hns3: add compatible handling for MAC VLAN switch parameter configuration

[Fred Kimmy]

[Bug Description]
Previously, hns3 driver just directly send specific setting bit
and mask bits of MAC VLAN switch parameter to the firmware, it
can not be compatible with the old firmware, because the old one
ignores mask bits and covers all bits with new setting bits.
So when running with old firmware, the communication between PF
and VF will fail after resetting or configuring spoof check, since
they will do the MAC VLAN switch parameter configuration.

[Steps to Reproduce]
1.using firmware which does not support 0x1033
2.send command 0x1033 to firmware

[Actual Results]
ping fail

[Expected Results]
ping ok

[Reproducibility]
Inevitably

[Additional information]
Hardware: D06
Firmware: NA
Kernel: NA

[Resolution]
This patch fixes this problem by reading switch parameter firstly,
then just modifies the corresponding bit and sends it to firmware.

71c5e83bcf1e net: hns3: add compatible handling for MAC VLAN switch parameter configuration

[Ike Panhc (ikepanhc)]

This patch fix dd2956eab104 ("net: hns3: not allow SSU loopback while execute ethtool -t dev"), which landed in mainline kernel since v5.4. This
is not needed for v4.15 based kernel.