rapidio: Fix kerneldoc and comment

This patch fix spelling typos found in DocBook/rapidio.xml
Ths file was generated from comments in the source files,
I had to fix them, instead of the xml file.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>