[PATCH v3 13/21] SecurityPkg/RngDxe: Replace Pcd with Sp80090Ctr256Guid

["PierreGondois" <pierre.gondois@arm.com>]

From: Pierre Gondois <pierre.gondois@arm.com>

gEfiRngAlgorithmSp80090Ctr256Guid was used as the default algorithm
in RngGetRNG(). The commit below set the default algorithm to
PcdCpuRngSupportedAlgorithm, which is a zero GUID by default.

As the Pcd value is not defined for any platform in the edk2-platfoms
repository, assume it was an error and go back to the first version,
using gEfiRngAlgorithmSp80090Ctr256Guid.

Fixes 4e5ecdbac8bd ("SecurityPkg: Add support for RngDxe on AARCH64")
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
---
 SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c b/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c
index 8d44f0636c3d..8cfe6b471192 100644
--- a/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c
+++ b/SecurityPkg/RandomNumberGenerator/RngDxe/Rand/RngDxe.c
@@ -126,8 +126,7 @@ ArchGetSupportedRngAlgorithms (
   OUT    EFI_RNG_ALGORITHM  *RNGAlgorithmList
   )
 {
-  UINTN              RequiredSize;
-  EFI_RNG_ALGORITHM  *CpuRngSupportedAlgorithm;
+  UINTN  RequiredSize;
 
   RequiredSize = 2 * sizeof (EFI_RNG_ALGORITHM);
 
@@ -136,9 +135,7 @@ ArchGetSupportedRngAlgorithms (
     return EFI_BUFFER_TOO_SMALL;
   }
 
-  CpuRngSupportedAlgorithm = PcdGetPtr (PcdCpuRngSupportedAlgorithm);
-
-  CopyMem (&RNGAlgorithmList[0], CpuRngSupportedAlgorithm, sizeof (EFI_RNG_ALGORITHM));
+  CopyMem (&RNGAlgorithmList[0], gEfiRngAlgorithmSp80090Ctr256Guid, sizeof (EFI_RNG_ALGORITHM));
 
   // x86 platforms also support EFI_RNG_ALGORITHM_RAW via RDSEED
   CopyMem (&RNGAlgorithmList[1], &gEfiRngAlgorithmRaw, sizeof (EFI_RNG_ALGORITHM));
-- 
2.25.1