staging: vt6656: rf.c clean up channel and power tables

Remove comments to channel number execpt where there is a
change to 5gHz channel 15

named comments are already referenced in revision history
in high-level comment.
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>