docs: Add details about required kernel versions above 4.9.17, supported OS update
docs: Add details about required kernel versions above 4.9.17, supported OS update

Fixes: #10534
Signed-off-by: Sean Winn <d7e19930cc1f42c2d0781f4d9e6f1fe5891bf9cf@isovalent.com>
Signed-off-by: Joe Stringer <16a9a54ddf4259952e3c118c763138e83693d7fd@cilium.io>
tklauser/cilium,cilium/cilium,tgraf/cilium,michi-covalent/cilium,michi-covalent/cilium,michi-covalent/cilium,tgraf/cilium,tgraf/cilium,cilium/cilium,tgraf/cilium,cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium-team/cilium,cilium/cilium,cilium-team/cilium,tgraf/cilium,tklauser/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,tgraf/cilium,tklauser/cilium