[XFS] clean up vnode/inode tracing

Simplify vnode tracing calls by embedding function name & return addr in
the calling macro.

Also do a lot of vnode->inode renaming for consistency, while we're at it.

SGI-PV: 970335
SGI-Modid: xfs-linux-melb:xfs-kern:29650a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>