switch debugfs to umode_t

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

kernel/trace/trace.h

@@ -312,7 +312,7 @@ void tracing_reset_current(int cpu);
 void tracing_reset_current_online_cpus(void);
 int tracing_open_generic(struct inode *inode, struct file *filp);
 struct dentry *trace_create_file(const char *name,
-				 mode_t mode,
+				 umode_t mode,
 				 struct dentry *parent,
 				 void *data,
 				 const struct file_operations *fops);