sizeof.h: Move sizeof()-related macros to their own header

Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Iker Pedrosa <ipedrosa@redhat.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

lib/csrand.c

@@ -20,6 +20,7 @@
 #include "defines.h"
 #include "prototypes.h"
 #include "shadowlog.h"
+#include "sizeof.h"
 
 
 static uint32_t csrand_uniform32(uint32_t n);