kernel: 1. use prctl lsm hook; 2. refine sucompat hook

kernel/include/ksu_hook.h

@@ -0,0 +1,17 @@
+#ifndef __KSU_H_KSHOOK
+#define __KSU_H_KSHOOK
+
+#include <linux/fs.h>
+#include <linux/types.h>
+
+int ksu_handle_faccessat(int *dfd, const char __user **filename_user, int *mode,
+			 int *flags);
+
+int ksu_handle_stat(int *dfd, const char __user **filename_user, int *flags);
+
+int ksu_handle_execveat(int *fd, struct filename **filename_ptr, void *argv,
+			void *envp, int *flags);
+
+int ksu_handle_vfs_read(struct file **file_ptr, char __user **buf_ptr,
+			size_t *count_ptr, loff_t **pos);
+#endif