pinctrl: meson-gxl: add tsin_a pins

Add Tsin A pins to bank DV and X.
We don't have a driver for the tsin yet but since the tsin A pinmux is
enabled by default at boot time, declaring this pinmux is required to
properly operate on GPIOX.

Without this change, GPIOX 8, 9, 10 and 11 can't be driven as GPIO output
as the tsin A seems to have priority.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>