ARM: pm: omap34xx: remove misleading comment and use of r9

The code alludes to r9 being used to indicate what was lost over the
suspend/resume transition.  However, although r9 is set, it is never
actually used.

Also, the comments before the code (which refer to the value of r9)
and the comments against the assignment of r9 contradict each other,
so just remove them to avoid confusion.

Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>