Revert "net: vxlan: use kfree_skb_reason() in vxlan_xmit()"

This reverts commit da1178c6 which is
commit b71a576e upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I8b02c08e76fa94de63ec3085a5398595a3157682
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>