Revert "vxlan: Refresh FDB 'updated' time upon 'NTF_USE'"

This reverts commit 300b4e8f which is
commit 40a9994f 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: I58eed687aa5651990bf75cb99411e69d0c3a7fcc
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>