SecurityPkg/RngDxe: Add Arm support of RngDxe

Bugzilla: 3668 (https://bugzilla.tianocore.org/show_bug.cgi?id=3668)

Add RngDxe support for Arm. This implementation uses the ArmTrngLib
to support the RawAlgorithm and doens't support the RNDR instruction.

To re-use the RngGetRNG(), RngGetInfo() and FreeAvailableAlgorithms()
functions, create Arm/AArch64 files which implement the arch specific
function GetAvailableAlgorithms(). Indeed, FEAT_RNG instruction is not
supported on Arm.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Jiewen Yao <jiewen.yao@intel.com>

SecurityPkg/RandomNumberGenerator/RngDxe/RngDxe.inf

@@ -28,7 +28,7 @@
 #
 # The following information is for reference only and not required by the build tools.
 #
-#  VALID_ARCHITECTURES           = IA32 X64 AARCH64
+#  VALID_ARCHITECTURES           = IA32 X64 AARCH64 ARM
 #
 
 [Sources.common]
@@ -41,10 +41,16 @@
   Rand/AesCore.c
   Rand/AesCore.h
 
-[Sources.AARCH64]
+[Sources.AARCH64, Sources.ARM]
   ArmRngDxe.c
   ArmTrng.c
 
+[Sources.AARCH64]
+  AArch64/AArch64Algo.c
+
+[Sources.ARM]
+  Arm/ArmAlgo.c
+
 [Packages]
   MdeModulePkg/MdeModulePkg.dec
   MdePkg/MdePkg.dec
@@ -59,7 +65,7 @@
   TimerLib
   RngLib
 
-[LibraryClasses.AARCH64]
+[LibraryClasses.AARCH64, LibraryClasses.ARM]
   ArmTrngLib
 
 [Guids]