octeontx2-pf: Fix netdev features settings

commit 6b9e5ab7c0b083b005d0a1e9b43a617136387361 from
git@git.assembla.com:cavium/WindRiver.linux.git

Upon boot, as per ethtool show-features, interface is in
loopback mode which is incorrect. Fix this by making sure LOOPBACK
feature flag is set only in 'netdev->features' and not in
'netdev->hw_features'.

Also fixed
- similar issue with RXALL feature flag
- set maximum number of gso segments for the VF
- remove MTU related comments which are not valid anymore

Fixes upstream commit
Fixes: fd9d7859 ("octeontx2-pf: Implement ingress/egress VLAN offload")

Change-Id: I88307a603d8b840e6e3a3e125cc43ba93ac66338
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/49017


Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Sunil Kovvuri Goutham <Sunil.Goutham@cavium.com>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>