Implement SMCCC_ARCH_SOC_ID SMC call

Implemented SMCCC_ARCH_SOC_ID call in order to get below
SOC information:

1. SOC revision
2. SOC version

Implementation done using below SMCCC specification document:
https://developer.arm.com/docs/den0028/c

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: Ie0595f1c345a6429a6fb4a7f05534a0ca9c9a48b
diff --git a/include/services/arm_arch_svc.h b/include/services/arm_arch_svc.h
index 1cb2038..5bbd8bb 100644
--- a/include/services/arm_arch_svc.h
+++ b/include/services/arm_arch_svc.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -9,7 +9,11 @@
 
 #define SMCCC_VERSION			U(0x80000000)
 #define SMCCC_ARCH_FEATURES		U(0x80000001)
+#define SMCCC_ARCH_SOC_ID		U(0x80000002)
 #define SMCCC_ARCH_WORKAROUND_1		U(0x80008000)
 #define SMCCC_ARCH_WORKAROUND_2		U(0x80007FFF)
 
+#define SMCCC_GET_SOC_VERSION		U(0)
+#define SMCCC_GET_SOC_REVISION		U(1)
+
 #endif /* ARM_ARCH_SVC_H */