util: Consolidate ARRAY_SIZE() definitions

ARRAY_SIZE() was defined several times around the code-base.
Provide a single definition in util.h and include it where necessary.

Change-Id: Idc4cf030969ffc7f0928c6897a23962a70adcf05
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>
diff --git a/test/test-client-escape.c b/test/test-client-escape.c
index b3083b7..e8020f7 100644
--- a/test/test-client-escape.c
+++ b/test/test-client-escape.c
@@ -21,6 +21,8 @@
 #include <stdio.h>
 #include <unistd.h>
 
+#include "util.h"
+
 static ssize_t __read(int fd, void *buf, size_t len);
 #define read __read
 #include "config.c"
@@ -154,8 +156,6 @@
 	},
 };
 
-#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
-
 struct test_ctx ctxs[ARRAY_SIZE(tests)];
 
 int write_buf_to_fd(int fd, const uint8_t *buf, size_t len)