sh4: Clean up includes

Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-28-git-send-email-peter.maydell@linaro.org
diff --git a/target-sh4/op_helper.c b/target-sh4/op_helper.c
index a312118..368e687 100644
--- a/target-sh4/op_helper.c
+++ b/target-sh4/op_helper.c
@@ -16,7 +16,7 @@
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
-#include <stdlib.h>
+#include "qemu/osdep.h"
 #include "cpu.h"
 #include "exec/helper-proto.h"
 #include "exec/cpu_ldst.h"