feat: update parameters to enable ESPI for FVP

Enable support for ESPI and increase the virtual interrupt count to
5120 to accommodate interrupts in extended range [4096, 5119].

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: I9aa5b12723743aa670688d4be2c52486b1e39598
diff --git a/BUILD.gn b/BUILD.gn
index a3423c9..d462c38 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -87,6 +87,7 @@
   console = "//src/arch/aarch64/pl011"
   iommu = "//src/arch/aarch64/arm_smmuv3"
   gic_version = 3
+  gic_enable_espi = 1
   gicd_base_address = "0x2f000000"
   gicr_base_address = "0x2f100000"
   gicr_frames = 8
@@ -104,7 +105,7 @@
     smmu_memory_size = "0x100000"
     enable_mte = "1"
     plat_log_level = "LOG_LEVEL_INFO"
-    plat_num_virtual_interrupts_ids = 1024
+    plat_num_virtual_interrupts_ids = 5120
   }
 }