plat: imx: add sdei support for i.MX8MM

Add sdei support for i.MX8MM, this is to let jailhouse Hypervisor
could use SDEI to do hypervisor management, after physical IRQ
has been disabled routing.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Change-Id: I5fd697fee22df151e13d0f1335e8ac8a7bae6189
diff --git a/plat/imx/imx8m/imx8mm/include/platform_def.h b/plat/imx/imx8m/imx8mm/include/platform_def.h
index f25ceb0..1041459 100644
--- a/plat/imx/imx8m/imx8mm/include/platform_def.h
+++ b/plat/imx/imx8m/imx8mm/include/platform_def.h
@@ -29,6 +29,11 @@
 #define PLAT_WAIT_RET_STATE		U(1)
 #define PLAT_STOP_OFF_STATE		U(3)
 
+#define PLAT_PRI_BITS			U(3)
+#define PLAT_SDEI_CRITICAL_PRI		0x10
+#define PLAT_SDEI_NORMAL_PRI		0x20
+#define PLAT_SDEI_SGI_PRIVATE		U(9)
+
 #define BL31_BASE			U(0x920000)
 #define BL31_LIMIT			U(0x940000)