pinctrl: renesas: r8a77965: Share QSPI pin group data

Pin groups qspi[01]_data2 are subsets of qspi[01]_data4.

This reduces kernel size by 32 bytes.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/725d18018c5899b33a20b8f898a421547b0bb6c5.1640269757.git.geert+renesas@glider.be