ARM: consolidate pen_release instead of having per platform definitions

Almost each SMP platform defines pen_release to manage booting secondary
CPUs. This of course clashes with the single zImage effort.

Add the pen_release definition to the ARM SMP code, and remove all others.
This should only be used by platforms which lack any kind of CPU power
management...

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/mach-msm/hotplug.c

@@ -15,8 +15,6 @@
 
 #include "core.h"
 
-extern volatile int pen_release;
-
 static inline void cpu_enter_lowpower(void)
 {
 	/* Just flush the cache. Changing the coherency is not yet