Merge branch 'mptcp-next'

Mat Martineau says:

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mptcp: Protocol in-use tracking and code cleanup

Here's a collection of commits from the MPTCP tree:

Patches 1-4 and 6 contain miscellaneous code cleanup for more consistent
use of helper functions, existing local variables, and better naming.

Patches 5, 7, and 9 add sock_prot_inuse tracking for MPTCP and an
associated self test.

Patch 8 modifies the mptcp_connect self test tool to exit on SIGUSR1
when in "slow mode".
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Signed-off-by: David S. Miller <davem@davemloft.net>