ARM: 8248/1: pm: remove outdated comment

As of commit abda1bd5 __cpu_suspend()
takes only 2 arguments, and those arguments are passed by the platform
code. This comment thus makes no sense, as cpu_suspend() is not actually
hiding any arguments.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>