- lmv_getattr_name() recognizes cross-node name and repeats getattr to proper

- lmv_getattr_name() recognizes cross-node name and repeats getattr to proper
  MDS node with gotten ino/generation couple
- warning for cross-node rename in lmv_rename(). it isn't implemented yet.
  hence, we'd like to know when we hit this path
- mdc_getattr_name() accepts empty name in order to support getattr by fid request
- mds_get_parent_child_locked() forces MDS_INODELOCK_LOOKUP to be used
  if found dentry points to another MDS node
- mea_name2idx() and raw_name2idx() checks for last not to be zero and warns if it's

NOTE: this should fix the cause of the test #5 failure