feat(fvp): add GICv5 support

Factors out GICv3 specific code and replace it with GICv5. This can be
selected with FVP_USE_GIC_DRIVER=FVP_GICV5. Specifically, the FCONF
logic does not apply to GICv5 as the bindings are completely different.

This patch does not include a device tree. This will be added at a later
date.

Change-Id: Ifd0c7b4e0bc2ea1e53a6779ab4c50c4aec39dafb
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
diff --git a/include/drivers/arm/gicv5.h b/include/drivers/arm/gicv5.h
index 786d0bb..d01d24b 100644
--- a/include/drivers/arm/gicv5.h
+++ b/include/drivers/arm/gicv5.h
@@ -164,6 +164,13 @@
 #define WAIT_FOR_IDLE_IWB_CR0(base)						\
 	WAIT_FOR_IDLE(base, iwb_cr0, IWB_CR0)
 
+#define WIRE_PROP_DESC(_id, _domain, _tm) \
+	{ \
+		.id = (_id), \
+		.domain = (_domain), \
+		.tm = (_tm), \
+	}
+
 struct gicv5_wire_props {
 	/* continuous wire ID as seen by the attached component */
 	uint32_t id;