Move includes to the file that actually uses them

This was spotted thanks to clang-format reordering the includes.
Even with the new config, it will include the header file for the
current source file first. Nevertheless, it is best to always include
header files where they are needed.

common/common-cpu.h

@@ -31,6 +31,9 @@ POSSIBILITY OF SUCH DAMAGE.
 
 #pragma once
 
+#include <sched.h>
+#include <stdlib.h>
+
 #define IS_CPU_PARK 0
 #define IS_CPU_PIN 1