ceph: avoid useless ceph_get_dentry_parent_inode() in ceph_rename()
ceph: avoid useless ceph_get_dentry_parent_inode() in ceph_rename()

This is just old_dir; no reason to abuse the dcache pointers.

Reported-by: Al Viro <viro.zeniv.linux.org.uk>
Signed-off-by: Sage Weil <6dd34506bbd5e58221bbb3e4732d97c91f02277b@inktank.com>
Reviewed-by: Yan, Zheng <45e2ee8c8b09e76a9d512320d4eb53c0cd9925c0@intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs