Switch ARM debuggerd over to <sys/user.h>.

Change-Id: I106d4e80a2e819f1d47ca81893340f567bb8b4d9

debuggerd/arm/machine.c

@@ -15,18 +15,15 @@
 ** limitations under the License.
 */
 
-#include <stddef.h>
+#include <errno.h>
 #include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <stdio.h>
-#include <errno.h>
-#include <sys/types.h>
 #include <sys/ptrace.h>
-
-#include <corkscrew/ptrace.h>
-
-#include <linux/user.h>
+#include <sys/types.h>
+#include <sys/user.h>
 
 #include "../utility.h"
 #include "../machine.h"