Always #include <sys/...>, not <linux/...>.

(cherry picked from commit 817721ac4c3f843e1f1e973ca3140c61701a511a)

Change-Id: Ie8801e15996ebea16bf70a98c73e4e70fb3a3340
diff --git a/rild/rild.c b/rild/rild.c
index 64508f4..33d25c4 100644
--- a/rild/rild.c
+++ b/rild/rild.c
@@ -30,7 +30,7 @@
 #include <cutils/properties.h>
 #include <cutils/sockets.h>
 #include <sys/capability.h>
-#include <linux/prctl.h>
+#include <sys/prctl.h>
 
 #include <private/android_filesystem_config.h>
 #include "hardware/qemu_pipe.h"