hfs: update timestamp on truncate()

The vfs takes care of updating mtime on ftruncate(), but on truncate() it
must be done by the module.

Link: http://lkml.kernel.org/r/e1611eda2985b672ed2d8677350b4ad8c2d07e8a.1539316825.git.ernesto.mnd.fernandez@gmail.com
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfs/inode.c

@@ -642,6 +642,8 @@ int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
 
 		truncate_setsize(inode, attr->ia_size);
 		hfs_file_truncate(inode);
+		inode->i_atime = inode->i_mtime = inode->i_ctime =
+						  current_time(inode);
 	}
 
 	setattr_copy(inode, attr);