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/lib/efi/efi_app.c b/lib/efi/efi_app.c
index 0047998..af5a878 100644
--- a/lib/efi/efi_app.c
+++ b/lib/efi/efi_app.c
@@ -9,6 +9,7 @@
  */
 
 #include <common.h>
+#include <cpu_func.h>
 #include <debug_uart.h>
 #include <dm.h>
 #include <errno.h>