OvmfPkg/RiscVVirt: Add PlatformBootManagerLib library

RISC-V Qemu Virt platfform needs the PlatformBootManagerLib similar
to the one in ArmVirtPlatform. Add the library in OvmfPkg/RiscVVirt
leveraging the one from Arm.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
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: Andrei Warkentin <andrei.warkentin@intel.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>

OvmfPkg/RiscVVirt/Library/PlatformBootManagerLib/PlatformBm.h

@@ -0,0 +1,45 @@
+/** @file
+  Head file for BDS Platform specific code
+
+  Copyright (C) 2015-2016, Red Hat, Inc.
+  Copyright (c) 2004 - 2008, Intel Corporation. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef _PLATFORM_BM_H_
+#define _PLATFORM_BM_H_
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DevicePathLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+/**
+  Download the kernel, the initial ramdisk, and the kernel command line from
+  QEMU's fw_cfg. Construct a minimal SimpleFileSystem that contains the two
+  image files, and load and start the kernel from it.
+
+  The kernel will be instructed via its command line to load the initrd from
+  the same Simple FileSystem.
+
+  @retval EFI_NOT_FOUND         Kernel image was not found.
+  @retval EFI_OUT_OF_RESOURCES  Memory allocation failed.
+  @retval EFI_PROTOCOL_ERROR    Unterminated kernel command line.
+
+  @return                       Error codes from any of the underlying
+                                functions. On success, the function doesn't
+                                return.
+**/
+EFI_STATUS
+EFIAPI
+TryRunningQemuKernel (
+  VOID
+  );
+
+#endif // _PLATFORM_BM_H_