dolphin: Show full KFileItem statusbar text with hovered folders too

This patch changes the status bar text dolphin shows when a folder is
hovered. It now shows full folder info, eg:
  "mydir (folder, symlink to /opt/mydir")
instead of:
  "mydir"
This is consistent with dolphin's behavior on regular files, and
DolphinPart already does that (DolphinPart::slotRequestItemInfo has no
special cases for folders).

CCBUG: 260717
REVIEW: 112106