UefiPayloadPkg: Handle simple reserved ranges from DT

DT has a way to provide reserved images in a simpler tabular
manner. UPL should be able to support that.

Signed-off-by: Dhaval Sharma <dhaval@rivosinc.com>

UefiPayloadPkg/Library/FdtParserLib/FdtParserLib.c

@@ -814,6 +814,9 @@ ParseDtb (
   UINT8                 NodeType;
   EFI_BOOT_MODE         BootMode;
   CHAR8                 *GmaStr;
+  INTN                  NumRsv;
+  EFI_PHYSICAL_ADDRESS  Addr;
+  UINT64                Size;
 
   Fdt               = FdtBase;
   Depth             = 0;
@@ -880,6 +883,16 @@ ParseDtb (
     }
   }
 
+  NumRsv = FdtNumRsv (Fdt);
+  /* Look for an existing entry and add it to the efi mem map. */
+  for (index = 0; index < NumRsv; index++) {
+    if (FdtGetMemRsv (Fdt, index, &Addr, &Size) != 0) {
+      continue;
+    }
+
+    BuildMemoryAllocationHob (Addr, Size, EfiReservedMemoryType);
+  }
+
   index = RootBridgeCount - 1;
   Depth = 0;
   for (Node = FdtNextNode (Fdt, 0, &Depth); Node >= 0; Node = FdtNextNode (Fdt, Node, &Depth)) {