Repair linked list management in Tcl_DeleteCloseHandler().
CloseCallback struct is used only locally.  Remove from tclInt.h.
Repair linked list management in Tcl_DeleteCloseHandler().
CloseCallback struct used only locally.  Remove from tclIO.h.
Repair linked list management in Tcl_DeleteCloseHandler().
CloseCallback struct used only locally.  Remove from tclIO.h.