staging: lustre: llite_lib.c Set ll_md_setattr function to be static

This fixes the following sparse warning:
llite_lib.c:1240:5: warning: symbol 'll_md_setattr' was not declared. Should it be static?
Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/llite_lib.c

@@ -1237,7 +1237,7 @@ void ll_clear_inode(struct inode *inode)
 	lli->lli_has_smd = false;
 }
 
-int ll_md_setattr(struct dentry *dentry, struct md_op_data *op_data,
+static int ll_md_setattr(struct dentry *dentry, struct md_op_data *op_data,
 		  struct md_open_data **mod)
 {
 	struct lustre_md md;