[PATCH] ppc32: small cpufreq update

This patch adds a missing attribute to pmac cpufreq so that
"scaling_available_frequencies" works.  It also cleans up the duplicate
definitions for low and high speed constants.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: John Clemens <clemej@alum.rpi.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>