UefiCpuPkg: Add RISCV_EFI_BOOT_PROTOCOL related definitions

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4076

RISC-V UEFI based platforms need to support RISCV_EFI_BOOT_PROTOCOL.
Add this protocol GUID definition and the header file required.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Daniel Schaefer <git@danielschaefer.me>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Abner Chang <abner.chang@amd.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Andrei Warkentin <andrei.warkentin@intel.com>
Acked-by: Ray Ni <ray.ni@intel.com>

UefiCpuPkg/Include/Protocol/RiscVBootProtocol.h

@@ -0,0 +1,34 @@
+/** @file
+  RISC-V Boot Protocol mandatory for RISC-V UEFI platforms.
+
+  @par Revision Reference:
+  The protocol specification can be found at
+  https://github.com/riscv-non-isa/riscv-uefi
+
+  Copyright (c) 2022, Ventana Micro Systems Inc. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef RISCV_BOOT_PROTOCOL_H_
+#define RISCV_BOOT_PROTOCOL_H_
+
+typedef struct _RISCV_EFI_BOOT_PROTOCOL RISCV_EFI_BOOT_PROTOCOL;
+
+#define RISCV_EFI_BOOT_PROTOCOL_REVISION  0x00010000
+#define RISCV_EFI_BOOT_PROTOCOL_LATEST_VERSION \
+        RISCV_EFI_BOOT_PROTOCOL_REVISION
+
+typedef
+EFI_STATUS
+(EFIAPI *EFI_GET_BOOT_HARTID)(
+  IN RISCV_EFI_BOOT_PROTOCOL   *This,
+  OUT UINTN                    *BootHartId
+  );
+
+typedef struct _RISCV_EFI_BOOT_PROTOCOL {
+  UINT64                 Revision;
+  EFI_GET_BOOT_HARTID    GetBootHartId;
+} RISCV_EFI_BOOT_PROTOCOL;
+
+#endif