refactor(errata_abi): add the Cortex-X4 cpu struct

Signed-off-by: Sona Mathew <sonarebecca.mathew@arm.com>
Change-Id: I8421dcc98eea85d038070f90e819e91bb2652727
(cherry picked from commit cd6128d479033c7ac4cff8e932415b5c04bbde67)
diff --git a/tftf/tests/runtime_services/standard_service/errata_abi/api_tests/test_errata_abi_functionality.c b/tftf/tests/runtime_services/standard_service/errata_abi/api_tests/test_errata_abi_functionality.c
index 4619b20..ed68b71 100644
--- a/tftf/tests/runtime_services/standard_service/errata_abi/api_tests/test_errata_abi_functionality.c
+++ b/tftf/tests/runtime_services/standard_service/errata_abi/api_tests/test_errata_abi_functionality.c
@@ -367,6 +367,14 @@
 	},
 };
 
+em_cpu_t cortex_X4_errata_list = {
+	.cpu_pn = 0xD82,
+	.cpu_errata = {
+		{2701112, 0x00, 0x00},
+		{-1}
+	},
+};
+
 em_cpu_t cortex_A715_errata_list = {
 	.cpu_pn = 0xD4D,
 	.cpu_errata = {
@@ -566,6 +574,12 @@
 		cpu_ptr = &cortex_A78_AE_errata_list;
 		break;
 	}
+	case 0xD82:
+	{
+		VERBOSE("MIDR matches Cortex-X4 -> %x\n", midr_val);
+		cpu_ptr =  &cortex_X4_errata_list;
+		break;
+	}
 	default:
 	{
 		ERROR("MIDR did not match any cpu\n");