Merge branch 'mptcp-sdeq-fixes'

Mat Martineau says:

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mptcp: 32-bit sequence number improvements

MPTCP-level sequence numbers are 64 bits, but RFC 8684 allows use of
32-bit sequence numbers in the DSS option to save header space. Those
32-bit numbers are the least significant bits of the full 64-bit
sequence number, so the receiver must infer the correct upper 32 bits.

These two patches improve the logic for determining the full 64-bit
sequence numbers when the 32-bit truncated version has wrapped around.
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Signed-off-by: David S. Miller <davem@davemloft.net>