pinctrl: sh-pfc: r8a7791: Remove bogus ctrl marks from qspi_data4_b group
The qspi_data4_b_mux[] array contains pin marks for the clock and chip
select pins. The qspi_data4_b_pins[] array rightfully does not contain
the corresponding pin numbers, as the control pins are provided by a
separate group (qspi_ctrl_b).