ARM: imx: compile fix for hotplug.c

Commit bca7a5a (ARM: cpu hotplug: remove majority of cache flushing
from platforms) removes include of <asm/cacheflush.h> and hence
discovers a few indirect inclusion and declaration problems as below.

  CC      arch/arm/mach-imx/hotplug.o
In file included from arch/arm/mach-imx/hotplug.c:16:0:
arch/arm/mach-imx/common.h💯29: warning: ‘struct pt_regs’ declared inside parameter list [enabled by default]
arch/arm/mach-imx/common.h💯29: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
arch/arm/mach-imx/common.h:101:29: warning: ‘struct pt_regs’ declared inside parameter list [enabled by default]
arch/arm/mach-imx/hotplug.c: In function ‘imx_cpu_die’:
arch/arm/mach-imx/hotplug.c:53:2: error: implicit declaration of function ‘cpu_do_idle’ [-Werror=implicit-function-declaration]
arch/arm/mach-imx/hotplug.c: In function ‘imx_cpu_kill’:
arch/arm/mach-imx/hotplug.c:58:26: error: ‘jiffies’ undeclared (first use in this function)
arch/arm/mach-imx/hotplug.c:58:26: note: each undeclared identifier is reported only once for each function it appears in
arch/arm/mach-imx/hotplug.c:58:2: error: implicit declaration of function ‘msecs_to_jiffies’ [-Werror=implicit-function-declaration]
arch/arm/mach-imx/hotplug.c:61:3: error: implicit declaration of function ‘time_after’ [-Werror=implicit-function-declaration]

Fix them by adding the needed inclusion and declaration.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Olof Johansson <olof@lixom.net>

arch/arm/mach-imx/common.h

@@ -12,6 +12,7 @@
 #define __ASM_ARCH_MXC_COMMON_H__
 
 struct platform_device;
+struct pt_regs;
 struct clk;
 enum mxc_cpu_pwr_mode;
 

arch/arm/mach-imx/hotplug.c

@@ -11,7 +11,9 @@
  */
 
 #include <linux/errno.h>
+#include <linux/jiffies.h>
 #include <asm/cp15.h>
+#include <asm/proc-fns.h>
 
 #include "common.h"