imx: add support for i.MX8MQ power domain controller

Add support for the power domain controller that's used on the
i.MX8MQ.  This will be needed to be able to power on the PCIe
controller.  Bindings taken from Linux, driver implementation
taken from the i.MX8 power domain controller and adjusted for
the i.MX8M SoC.

Signed-off-by: Patrick Wildt <patrick@blueri.se>
diff --git a/include/imx_sip.h b/include/imx_sip.h
index fbb6c5e..139ff61 100644
--- a/include/imx_sip.h
+++ b/include/imx_sip.h
@@ -6,6 +6,9 @@
 #ifndef _IMX_SIP_H__
 #define _IMX_SIP_H_
 
+#define IMX_SIP_GPC		0xC2000000
+#define  IMX_SIP_GPC_PM_DOMAIN	0x03
+
 #define IMX_SIP_SRC		0xC2000005
 #define IMX_SIP_SRC_M4_START	0x00
 #define IMX_SIP_SRC_M4_STARTED	0x01