Merge branch 'net-make-udp-tunnel-devices-support-fraglist'

Xin Long says:

====================
net: make udp tunnel devices support fraglist

Like GRE device, UDP tunnel devices should also support fraglist, so
that some protocol (like SCTP) HW GSO that requires NETIF_F_FRAGLIST
in the dev can work. Especially when the lower device support both
NETIF_F_GSO_UDP_TUNNEL and NETIF_F_GSO_SCTP.
====================

Link: https://lore.kernel.org/r/cover.1610704037.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>