To fix bug 1722584 we inserted a checksum-fill rule for
metadata proxy replies. Recent kernels have disabled
this support for TCP because it was invalid, and
supposedly not doing anything, so let's get ahead of
things and remove the code.
Kernel mailing list discussion is at
https://lore.kernel.org/patchwork/patch/824819/
Partially reverts ed1c3b021751273e427d47fcf544c56bdabf97bb
Change-Id: Ib7cc8f82a91972f17987fb95130edc4069d9423f
Related-bug: #1722584
b1b8a438fe