0 -> NULL
MGET -> m_get
No functional change.
MGET -> m_get
add hardware acceleration
For now this supports only GeForce2 MX cards but most NV1x chips should work
once their PCI iDs are added to gffb_match()
Tested only on macppc.
Follow OpenGroup online specification[1], move
fchmodat/mkdirat/mkfifoat/mknodat prototypes to <sys.stat.h>.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/sys_stat.h.html
some cleanup:
- use macros to shorten a while lot of bus_space_write_4() lines
- update some comments
- remove debug goop and cargo culted leftovers
support WSDISPLAYIO_GET_FBINFO
PR/48292: Justin Cormack: paccept creates sockets that cannot be made blocking
Reset the socket flags not just the file flags for non-blocking I/O.
XXX: pullup 6
- initialize m_len m_pkthgr.len to 0 in constructors, as discussed in tech-net.
- s/MGET/m_get
- s/0/NULL
delete extra m_len initialization.
Use MACHINE_CPU for m68k.  Use similar logic for both tests.