ARM64: Make ARCH_NR_GPIO a Kconfig variable

Have ARCH_NR_GPIO configurable in ARM64 similar to how it
is in ARM.

Change-Id: I7b292a9f2cb8925382a6478a52e85f831ddbc123
Signed-off-by: Kyle Yan <kyan@codeaurora.org>
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 3aff389..820c23d2 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -606,6 +606,18 @@
 	  Say Y here to experiment with turning CPUs off and on.  CPUs
 	  can be controlled through /sys/devices/system/cpu.
 
+# The GPIO number here must be sorted by descending number. In case of
+# a multiplatform kernel, we just want the highest value required by the
+# selected platforms.
+config ARCH_NR_GPIO
+	int
+	default 1024 if ARCH_QCOM
+	default 256
+	help
+	  Maximum number of GPIOs in the system.
+
+	  If unsure, leave the default value.
+
 # Common NUMA Features
 config NUMA
 	bool "Numa Memory Allocation and Scheduler Support"