Really two patch series in one. The first two patches remove the
bitfield based superblock update method and replace it with a simple
"update and log everything" operation. Superblock updates are
now relatively rare so there's no need to optimise for single field
updates. This patchset removes all that complex code and makes
everything nice and simple.
The last 4 patches clean up some old macros that are only used once
or twice and that allows us to remove the xfs_vnode.h file. One more
historical reference derived from Irix vnodes is now gone...
Comments, flames, testing all welcome.