arm64: dts: renesas: white-hawk-ard-audio: Fix TPU0 groups

White Hawk ARD audio uses a clock generated by the TPU, but commit
3d144ef1 ("pinctrl: renesas: r8a779g0: Fix TPU suffixes") renamed
pin group "tpu_to0_a" to "tpu_to0_b".  Update DTS accordingly otherwise
the sound driver does not receive a clock signal.

Fixes: 3d144ef1 ("pinctrl: renesas: r8a779g0: Fix TPU suffixes")
Signed-off-by: Thuan Nguyen <thuan.nguyen-hong@banvien.com.vn>
Signed-off-by: Duy Nguyen <duy.nguyen.rh@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/TYCPR01MB8740608B675365215ADB0374B49CA@TYCPR01MB8740.jpnprd01.prod.outlook.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>