Merge branch 'mptcp-miscellaneous-changes-for-5-17'

Mat Martineau says:

====================
mptcp: Miscellaneous changes for 5.17

These are three unrelated patches that we've been testing in the MPTCP
tree.

Patch 1 modifies the packet scheduler that picks which TCP subflow is
used for each chunk of outgoing data. The updated scheduler improves
throughput on multiple-subflow connections.

Patch 2 updates a selftest to verify recent TCP_ULP sockopt changes
on MPTCP fallback sockets.

Patch 3 cleans up some unnecessary comparisons with an 8-bit value.
====================

Link: https://lore.kernel.org/r/20211217233702.299461-1-mathew.j.martineau@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>