Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC: r243857 (partial)

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags in sys/dev.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Give MEXTADD() another argument to make both void pointers to the
free function controlable, instead of passing the KVA of the buffer
storage as the first argument.

Fix all conventional users of the API to pass the KVA of the buffer
as the first argument, to make this a no-op commit.

Likely break the only non-convetional user of the API, after informing
the relevant committer.

Update the mbuf(9) manual page, which was already out of sync on
this point.

Bump __FreeBSD_version to 800016 as there is no way to tell how
many arguments a CPP macro needs any other way.

This paves the way for giving sendfile(9) a way to wait for the
passed storage to have been accessed before returning.

This does not affect the memory layout or size of mbufs.

Parental oversight by: sam and rwatson.

No MFC is anticipated.

Replace m_extadd() with macro version MEXTADD().

Stop embedding struct ifnet at the top of driver softcs. Instead the
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.

Reviewed by: sobomax, sam

Start each of the license/copyright comments with /*-, minor shuffle of lines

Eliminate multiple __FBSDID and sys/cdefs.h.

Use __FBSDID().
Also some minor style cleanups.

Honor the ATMIO_FLAG_ASYNC for asynchronuous open/close of VCs.

Inline a function that gcc refused to inline. This function was used
only in one place and it just served as semantic sugar.

This is a driver for IDT77252 based ATM interfaces. It has been tested
with a ProATM-155 and an IDT evaluation board and should also work
with a ProATM-25 (it seems to work at least, I cannot really measure
what the card emits). The driver has been tested on i386 and sparc64,
but should work an other archs also. It supports UBR, CBR, ABR and VBR;
AAL0, AAL5 and AALraw. As an additional feature VCI/VPI 0/0 can be
opened for receiving in AALraw mode and receives all cells not claimed
by other open VCs (even cells with invalid GFC, VPI and VCI fields and
OAM cells).

Thanks to Christian Bucari from ProSum for lending two cards and answering
my questions.