Add test case for SMCCC_ARCH_SOC_ID feature

Added test case for "SMCCC_ARCH_SOC_ID" SMC call.
This SMC call is used to retrieve SOC version and SOC revision

Test execution output is as below:

> Executing 'SMCCC_ARCH_SOC_ID test'
  TEST COMPLETE                                                 Passed
SOC Rev is not implemented
SOC Ver = 0x43b0000

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I48668ce22bb5d5767dadb42ce9526d77fd916bed
diff --git a/include/runtime_services/arm_arch_svc.h b/include/runtime_services/arm_arch_svc.h
index 12358f8..36b4448 100644
--- a/include/runtime_services/arm_arch_svc.h
+++ b/include/runtime_services/arm_arch_svc.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, Arm Limited. All rights reserved.
+ * Copyright (c) 2018-2020, Arm Limited. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,6 +9,7 @@
 
 #define SMCCC_VERSION		0x80000000
 #define SMCCC_ARCH_FEATURES	0x80000001
+#define SMCCC_ARCH_SOC_ID	0x80000002
 #define SMCCC_ARCH_WORKAROUND_1	0x80008000
 #define SMCCC_ARCH_WORKAROUND_2	0x80007FFF