MdeModulePkg: Add Capsule On Disk APIs into CapsuleLib.

REF: https://github.com/tianocore/tianocore.github.io/wiki/
UEFI-Capsule-on-Disk-Introducation

CoDCheckCapsuleOnDiskFlag() is to check if CapsuleOnDisk flag in
"OsIndications" Variable is enabled. It is used to indicate whether
capsule on disk is provisioned in normal boot path.

CoDClearCapsuleOnDiskFlag() is to to clear CapsuleOnDisk flags,
including "OsIndications" and "BootNext" variable.

CoDRelocateCapsule() is to relocate the capsules from EFI system
partition. Depends on PcdCapsuleInRamSupport, there are two solutions
to relocate the capsule on disk images:
When Capsule In Ram is supported, the Capsule On Disk images are
relocated into memory, and call UpdateCapsule() service to deliver
the capsules.
When Capsule In Ram is not supported, the Capsule On Disk images are
relocated into a temp file which will be stored in root directory on
a platform specific storage device. CapsuleOnDiskLoadPei PEIM will
retrieve the capsules from the relocation temp file and report
capsule hobs for them.

CoDRemoveTempFile() is to remove the relocation temp file in the next
boot after capsules are processed.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Chao B Zhang <chao.b.zhang@intel.com>
Signed-off-by: Wei6 Xu <wei6.xu@intel.com>
Reviewed-by: Chao B Zhang <chao.b.zhang@intel.com>
Acked-by: Hao A Wu <hao.a.wu@intel.com>

MdeModulePkg/Library/DxeCapsuleLibNull/DxeCapsuleLibNull.c

@@ -1,7 +1,7 @@
 /** @file
   Null Dxe Capsule Library instance does nothing and returns unsupport status.
 
-Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2007 - 2019, Intel Corporation. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -85,3 +85,86 @@ ProcessCapsules (
   return EFI_UNSUPPORTED;
 }
 
+
+/**
+  This routine is called to check if CapsuleOnDisk flag in OsIndications Variable
+  is enabled.
+
+  @retval TRUE     Flag is enabled
+  @retval FALSE    Flag is not enabled
+
+**/
+BOOLEAN
+EFIAPI
+CoDCheckCapsuleOnDiskFlag(
+  VOID
+  )
+{
+  return FALSE;
+}
+
+/**
+  This routine is called to clear CapsuleOnDisk flags including OsIndications and BootNext variable.
+
+  @retval EFI_SUCCESS   All Capsule On Disk flags are cleared
+
+**/
+EFI_STATUS
+EFIAPI
+CoDClearCapsuleOnDiskFlag(
+  VOID
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Relocate Capsule on Disk from EFI system partition.
+
+  Two solution to deliver Capsule On Disk:
+  Solution A: If PcdCapsuleInRamSupport is enabled, relocate Capsule On Disk to memory and call UpdateCapsule().
+  Solution B: If PcdCapsuleInRamSupport is disabled, relocate Capsule On Disk to a platform-specific NV storage
+  device with BlockIo protocol.
+
+  Device enumeration like USB costs time, user can input MaxRetry to tell function to retry.
+  Function will stall 100ms between each retry.
+
+  Side Effects:
+    Capsule Delivery Supported Flag in OsIndication variable and BootNext variable will be cleared.
+    Solution B: Content corruption. Block IO write directly touches low level write. Orignal partitions, file
+  systems of the relocation device will be corrupted.
+
+  @param[in]    MaxRetry             Max Connection Retry. Stall 100ms between each connection try to ensure
+                                     devices like USB can get enumerated. Input 0 means no retry.
+
+  @retval EFI_SUCCESS   Capsule on Disk images are successfully relocated.
+
+**/
+EFI_STATUS
+EFIAPI
+CoDRelocateCapsule(
+  UINTN     MaxRetry
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Remove the temp file from the root of EFI System Partition.
+  Device enumeration like USB costs time, user can input MaxRetry to tell function to retry.
+  Function will stall 100ms between each retry.
+
+  @param[in]    MaxRetry             Max Connection Retry. Stall 100ms between each connection try to ensure
+                                     devices like USB can get enumerated. Input 0 means no retry.
+
+  @retval EFI_SUCCESS   Remove the temp file successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+CoDRemoveTempFile (
+  UINTN    MaxRetry
+  )
+{
+  return EFI_UNSUPPORTED;
+}