pinctrl: uniphier: Divide pinmux group to support 1ch and 2ch I2S

pinctrl: uniphier: Divide pinmux group to support 1ch and 2ch I2S

Current pinmux group for audio in/out assumes 4ch I2S case but the
UniPhier AIO hardware also supports 1ch and 2ch I2S. So divide current
ain1 group into ain1, ain1_dat2 and ain1_dat4 groups. Divide other
ain and aout in the same way.

Signed-off-by: Ryuta NAKANISHI <nakanishi.ryuta@socionext.com>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Link: https://lore.kernel.org/r/1643376903-18623-3-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>