move ARRAY_SIZE macro to types.h

The ARRAY_SIZE macro was defined in several target files, so move it
to types.h.

This patch also removes two other identical macros: DIM (from jtag.h)
and asizeof (from arm11.h).

src/target/arm11.h

@@ -25,8 +25,6 @@
 
 #include "armv4_5.h"
 
-#define asizeof(x)	(sizeof(x) / sizeof((x)[0]))
-
 #define NEW(type, variable, items)			\
 	type * variable = calloc(1, sizeof(type) * items)