power: domain: add SCMI driver

Add power domain driver based on SCMI power domain management protocol.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
diff --git a/drivers/power/domain/Kconfig b/drivers/power/domain/Kconfig
index 411c210..bd82d2f 100644
--- a/drivers/power/domain/Kconfig
+++ b/drivers/power/domain/Kconfig
@@ -83,6 +83,13 @@
 	  simply accepts requests to power on/off various HW modules without
 	  actually doing anything beyond a little error checking.
 
+config SCMI_POWER_DOMAIN
+	bool "Enable SCMI power domain driver"
+	depends on POWER_DOMAIN && SCMI_FIRMWARE
+	help
+	  Enable power domain implementation based on SCMI power domain
+	  management protocol.
+
 config TEGRA186_POWER_DOMAIN
 	bool "Enable Tegra186 BPMP-based power domain driver"
 	depends on TEGRA186_BPMP