GIC: Add API to set interrupt routing

SPIs can be routed to either a specific PE, or to any one of all
available PEs.

API documentation updated.

Change-Id: I28675f634568aaf4ea1aa8aa7ebf25b419a963ed
Co-authored-by: Yousuf A <yousuf.sait@arm.com>
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
diff --git a/drivers/arm/gic/v2/gicv2_helpers.c b/drivers/arm/gic/v2/gicv2_helpers.c
index 7cdbc27..2693076 100644
--- a/drivers/arm/gic/v2/gicv2_helpers.c
+++ b/drivers/arm/gic/v2/gicv2_helpers.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -72,15 +72,6 @@
 	mmio_write_32(base + GICD_SPENDSGIR + (n << 2), val);
 }
 
-/*
- * Accessor to write the GIC Distributor ITARGETSR corresponding to the
- * interrupt `id`.
- */
-void gicd_set_itargetsr(uintptr_t base, unsigned int id, unsigned int target)
-{
-	mmio_write_8(base + GICD_ITARGETSR + id, target & GIC_TARGET_CPU_MASK);
-}
-
 /*******************************************************************************
  * Get the current CPU bit mask from GICD_ITARGETSR0
  ******************************************************************************/