arm64: meson: remove MESON_IRQ_GPIO selection

Selecting MESON_IRQ_GPIO forces it as built-in, but we may need to build it
as a module, thus remove it here and let the "default ARCH_MESON" build as
built-in by default with the option to switch it to module.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210902134914.176986-3-narmstrong@baylibre.com