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 <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-roiwxwgwgld4kygn65if60wa@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/objtool/builtin-check.c

@@ -36,8 +36,7 @@
 #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

@@ -31,11 +31,10 @@
 #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;
 	int (*fn)(int, const char **);