cbe_cpufreq cleanups:

* comment format
* whitespace
* don't init on non-cell platforms
Signed-off-by: NOlof Johansson <olof@lixom.net>
Acked-by: NChristian Krafft <krafft@de.ibm.com>
Signed-off-by: NArnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>