mptcp: rebase to Linux 6.7
JIRA: https://issues.redhat.com/browse/RHEL-15036 Tested: LNST, Tier1, selftests, pktdrill
Rebase to the current upstream to bring in new features and a lot of fixes. A good half of the long commit list touches the self-tests only, and the remaining is self-contained in mptcp.
The only notable exception is:
tcp: get rid of sysctl_tcp_adv_win_scale
that is a pre requisite to a bunch of mptcp changes included here and also uncontroversially a good thing (TM) for TCP.
Wider-scope data-races related changeset are included (possibly as partial backport) only if they help to reduce conflict on later changes.
Signed-off-by: Paolo Abeni pabeni@redhat.com