net: stmmac: move check for hardware checksum supported

net: stmmac: move check for hardware checksum supported

Add a check in .ndo_features_check() to indicate whether hardware
checksum can be performed on the skbuff. Where hardware checksum is
not supported - either because the channel does not support Tx COE
or the skb isn't suitable (stmmac uses a tighter test than
can_checksum_protocol()) we also need to disable TSO, which will be
done by harmonize_features() in net/core/dev.c

This fixes a bug where a channel which has COE disabled may still
receive TSO skbuffs.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1w7pte-0000000EatU-0ILt@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>