common: Move reset_cpu() to the CPU header

Move this function out of common.h and into a relevant header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-omap2/omap5/hwinit.c b/arch/arm/mach-omap2/omap5/hwinit.c
index 56458ce..3b17330 100644
--- a/arch/arm/mach-omap2/omap5/hwinit.c
+++ b/arch/arm/mach-omap2/omap5/hwinit.c
@@ -12,6 +12,7 @@
  *	Sricharan	<r.sricharan@ti.com>
  */
 #include <common.h>
+#include <cpu_func.h>
 #include <palmas.h>
 #include <asm/armv7.h>
 #include <asm/arch/cpu.h>