block[08|09|10]/init.c: Include <stdlib.h> to fix warning on exit()

testsuites/libtests/block08/init.c

@@ -24,6 +24,8 @@
 
 #include "bdbuf_tests.h"
 
+#include <stdlib.h> /* for exit */
+
 const char rtems_test_name[] = "BLOCK 8";
 
 rtems_task Init(rtems_task_argument argument)

testsuites/libtests/block09/init.c

@@ -26,6 +26,7 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include <rtems.h>
 #include <rtems/bdbuf.h>

testsuites/libtests/block10/init.c

@@ -25,6 +25,7 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <stdlib.h>
 
 #include <rtems.h>
 #include <rtems/bdbuf.h>