tty: serial: sh-sci: Fix end of transmission on SCI

We need to set TE to "0" (i.e., disable serial transmission) to
get the expected behavior of the end of serial transmission.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230412145053.114847-6-biju.das.jz@bp.renesas.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>