soc: qcom: add build infrastructure

Add Kconfig / Makefiles to build rpmh and cmd-db drivers.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index cee506f..8ef408d 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -48,6 +48,7 @@
 	  This allows other drivers to verify the SoC familiy & revision using
 	  matching SoC attributes.
 
+source "drivers/soc/qcom/Kconfig"
 source "drivers/soc/samsung/Kconfig"
 source "drivers/soc/ti/Kconfig"