MFC r260016:

Remove superfluous old-style rcsid[] from if_sk.c.  There is already an
__FBSDID() at the top of the file.
MFC r260038:

In sys/dev/en/midway.c, #if 0 an unused static function.
MFC r260040:

In sys/dev/mcd/mcd.c, mark the static const COPYRIGHT string as __used,
so it ends up in the object file, and no warnings are emitted about it
being actually unused.
MFC r260042:

Remove superfluous old-style rcsid[] from if_my.c.  There is already an
__FBSDID() at the top of the file.
MFC r260048:

In sys/netgraph/netflow, use __FBSDID() instead of old-style rcs_id[].
MFC r260057:

In sys/dev/scc, remove unused static function scc_setmreg().  While
here, invoke scc_getmreg() in two more places where it can be used.

Reviewed by:	marcel
MFC r260103:

In sys/amd64/amd64/pmap.c, remove static function pmap_is_current(),
which has been unused since r189415.

Reviewed by:	alc
MFC r260095:

For sys/boot/i386 and sys/boot/pc98, separate flags to be passed
directly to the linker (LD_FLAGS) from flags passed indirectly, via the
compiler driver (LDFLAGS).

This is because several Makefiles under sys/boot/i386 and sys/boot/pc98
use ${LD} directly to link, and the normal LDFLAGS value should not be
used in these cases.
MFC r260112:

In sys/dev/sound/pci/maestro.c, #if 0 two unused static functions.
MFC Broadcom 10Gb bxe driver
Merged r255736, r255861, r256299, r256341, r258187, r259928, r260113

Approved by:  davidch (mentor)
MFC r258821 - fix tcp simultaneous close

PR:             kern/99188
Merged r260415 from head.

Approved by:	davidch
Revert MFC of r258821 - it was already handled by MFC of r239672.

Pointy hat to: peter