[PATCH] Revert ABI-breaking change in /proc

Some user tools parse /proc/scsi/scsi, so we can't yet change the names.
Change the existing ones back to their old names, and add an admonition
to not make the same mistake that I did.

Andrew Morton reports that this was breaking YDL 4.1 userspace.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>