Revert "vxlan: Fix NPD when refreshing an FDB entry with a nexthop object"

This reverts commit 4ff4f310 which is
commit 6ead3814 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: I44d68db45be3e52593bcb42ca590bc2bd64f0d0f
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>