objtool: Drop ARRAY_SIZE() definition, tools/include/linux/kernel.h has it now

And with the goodies present in the kernel.h counterpart, i.e. checking
that the parameter is an array at build time.

Cc: Adrian Hunter <[e-mail]>
Cc: David Ahern <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Josh Poimboeuf <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Wang Nan <[e-mail]>
Link: http://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/objtool/builtin-check.c

···
 #include "warn.h"
 
 #include <linux/hashtable.h>
-
-#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#include <linux/kernel.h>
 
 #define STATE_FP_SAVED		0x1
 #define STATE_FP_SETUP		0x2

tools/objtool/objtool.c

···
 #include <stdlib.h>
 #include <subcmd/exec-cmd.h>
 #include <subcmd/pager.h>
+#include <linux/kernel.h>
 
 #include "builtin.h"
-
-#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
 
 struct cmd_struct {
 	const char *name;