Rename dup3110 to dup3100 to match historical practice for NetBSD-11,
because we already have kevent100. Fix compat_dup3 to belong in compat_100
not compat_110.

version dup3

Modularize the COMPAT_90 code that resulted from the removal of
netinet6/nd6 from the kernel. Now, the minimal compat code can
be successfully loaded and unloaded along with the rest of the
COMPAT_90 code.

XXX pullup-10 - hopefully before RC2

Add linux waitid(2) from GSoC 2023 (Theodore Preduta)

Add epoll(2) from Theodore Preduta as part of GSoC 2023

Create compat_100 module infrastructure now that we have branched
for NetBSD-10

branches: 1.6.26;
Add a new member to struct vfsstat and grow the unused members
The new member is caled f_mntfromlabel and it is the dkw_wname
of the corresponding wedge. This is now used by df -W to display
the mountpoint name as NAME=

The max subtype of the ifmedia word is 31. It's too small for Ethernet now.
We currently use use it up to 30. We should extend the limit to be able to use
more than 10Gbps speeds. Our ifmedia(4) is inconvenience and have some problem
so we should redesign the interface, but it's too late for netbsd-9 to do it.
So, we keep the data structure size and modify the structure a bit. The
strategy is almost the same as FreeBSD. Many bits of IFM_OMASK for Ethernet
have not used, so use some of them for Ethernet's subtype.

The differences against FreeBSD are:
- We use NetBSD style compat code (i.e. no SIOCGIFXMEDIA).
- FreeBSD's IFM_ETH_XTYPE's bit location is from 11 to "14" even though
IFM_OMASK is from 8 to "15". We use _IFM_ETH_XTMASK from bit 13 to "15".
- FreeBSD changed the meaning of IFM_TYPE_MATCH(). I think we should
not do it. We keep it not changing and added new IFM_TYPE_SUBTYPE_MATCH()
macro for matching both TYPE and SUBTYPE.
- Added up to 400GBASE-SR16.

New layout of the media word is as follows (from ifmedia_h):

* if_media Options word:
* Bits Use
* ---- -------
* 0-4 Media subtype MAX SUBTYPE == 255 for ETH and 31 for others
* 5-7 Media type
* 8-15 Type specific options
* 16-18 Mode (for multi-mode devices)
* 19 (Reserved for Future Use)
* 20-27 Shared (global) options
* 28-31 Instance
*
* 3 2 1
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
* +-------+---------------+-+-----+---------------+-----+---------+
* | | |R| | | | |
* | IMASK | GMASK |F|MMASK+-----+ OMASK |NMASK| TMASK |
* | | |U| |XTMSK| | | |
* +-------+---------------+-+-----+-----+---------+-----+---------+
* <-----> <---> <--->
* IFM_INST() IFM_MODE() IFM_TYPE()
*
* IFM_SUBTYPE(other than ETH)<------->
*
* <---> IFM_SUBTYPE(ETH)<------->
*
*
* <-------------> <------------->
* IFM_OPTIONS()

Split the COMPAT_50 socket-timeout stuff out of kern/uipc_socket.c
and into its own source file, which is now included in the compat_50
module.

(Not sure how this got missed during the original [pgoyette-compat] work)

- provide a hook for the 43 tty ioctls
- make the 60 tty ioctl hook look the same
- fix the tty code to call both hooks and remove unused lock

Merge the [pgoyette-compat] branch

branches: 1.1.4; 1.1.6; 1.1.16; 1.1.42; 1.1.44;
Move boottime50 and its associated sysctl into the compat module. As
noted on tech-kern. Should fix PR/47579.

OK christos@

Will request pull-up to 6.0 in a few days.