ARM: berlin: add the LIBGPIO as a dependency for the BG2Q

The BG2Q has GPIOs driven by the dwapb GPIO driver. Add the LIBGPIO as a
dependency to be able to support them.
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Reviewed-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>

arch/arm/mach-berlin/Kconfig

 config ARCH_BERLIN
 	bool "Marvell Berlin SoCs" if ARCH_MULTI_V7
+	select ARCH_REQUIRE_GPIOLIB
 	select ARM_GIC
 	select GENERIC_IRQ_CHIP
 	select DW_APB_ICTL