feat(interrupts): introduce a new paravirtualized interface

This patch adds basic support for a new paravirtualized interface that
allows an SP to reconfigure an interrupt, it owns, in runtime. Further
patches will add the complete support.

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: I45ad89d177da3303fc413f250e44e4c1ca1bf9dc
diff --git a/src/arch/aarch64/hypervisor/handler.c b/src/arch/aarch64/hypervisor/handler.c
index 572c8b8..ab7f9a1 100644
--- a/src/arch/aarch64/hypervisor/handler.c
+++ b/src/arch/aarch64/hypervisor/handler.c
@@ -1065,6 +1065,11 @@
 		vcpu->regs.r[0] = plat_ffa_interrupt_deactivate(
 			args.arg1, args.arg2, vcpu);
 		break;
+
+	case HF_INTERRUPT_RECONFIGURE:
+		vcpu->regs.r[0] = plat_ffa_interrupt_reconfigure(
+			args.arg1, args.arg2, args.arg3, vcpu);
+		break;
 #endif
 
 	default: