lib: utils/gpio: Use kconfig for enabling/disabling drivers

We update gpio drivers makefile to use kconfig for enabling/disabling
drivers. To avoid compile errors, we also enable appropriate gpio
drivers for each platform.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Tested-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Atish Patra <atishp@rivosinc.com>
Tested-by: Atish Patra <atishp@rivosinc.com>

lib/utils/gpio/Kconfig

@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: BSD-2-Clause
+
+menu "GPIO Support"
+
+config FDT_GPIO
+	bool "FDT based GPIO drivers"
+	select GPIO
+	default n
+
+if FDT_GPIO
+
+config FDT_GPIO_SIFIVE
+	bool "SiFive GPIO FDT driver"
+	default n
+
+endif
+
+config GPIO
+	bool "GPIO support"
+	default n
+
+endmenu