arm64: Kconfig: meson: drop pinctrl

Don't automatically select pinctrl drivers, leave it up to defaults in
drivers/pinctrl/meson, which default to built-in, but are also now
optionally configurable as modules as of
commit 9c65441e ("pinctrl/meson: enable building as modules")

Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://lore.kernel.org/r/20201207230156.10198-1-khilman@baylibre.com

'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>