[POWERPC] PS3: Sys-manager code cleanup

General code cleanups for PS3 system-manager:
 o Move all MODULE_ macros to bottom.
 o Correct PS3_SM_WAKE_P_O_R value.
 o Enhance comment on wakeup source values.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>