[PATCH] Doc/MSI-HOWTO: cleanups

Clean up typos, kernel function interfaces, acronyms, add whitespace,
improve readability.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>