orangefs: user current_user_ns() for uids/gids passed in from userspace

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs: remove pvfs2_update_inode_time

Call the proper function to get the VFS timestamp instead of the
hidden assignment of CURRENT_TIME.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>