Use dedicated GUID for DUMMYOS boot protocol

sdk/xtdk/xtguid.h

@@ -20,6 +20,7 @@
 
 /* EFI XT boot protocols GUIDs */
 #define XT_CHAIN_BOOT_PROTOCOL_GUID          {0x58544F53, 0x5854, 0x4357, {0x00, 0x43, 0x48, 0x41, 0x49, 0x4E, 0x50, 0x54}}
+#define XT_DUMMY_BOOT_PROTOCOL_GUID          {0x58544F53, 0x5854, 0x4357, {0x00, 0x44, 0x55, 0x4D, 0x4D, 0x59, 0x50, 0x54}}
 #define XT_LINUX_BOOT_PROTOCOL_GUID          {0x58544F53, 0x5854, 0x4357, {0x00, 0x4C, 0x49, 0x4E, 0x55, 0x58, 0x50, 0x54}}
 #define XT_WINNT_BOOT_PROTOCOL_GUID          {0x58544F53, 0x5854, 0x4357, {0x00, 0x57, 0x49, 0x4E, 0x4E, 0x54, 0x50, 0x54}}
 #define XT_XTOS_BOOT_PROTOCOL_GUID           {0x58544F53, 0x5854, 0x4357, {0x00, 0x00, 0x58, 0x54, 0x4F, 0x53, 0x50, 0x54}}

xtldr/modules/dummy/dummy.c

@@ -50,7 +50,7 @@ EFI_STATUS
 XtLdrModuleMain(IN EFI_HANDLE ImageHandle,
                 IN PEFI_SYSTEM_TABLE SystemTable)
 {
-    EFI_GUID DummyGuid = XT_XTOS_BOOT_PROTOCOL_GUID;
+    EFI_GUID DummyGuid = XT_DUMMY_BOOT_PROTOCOL_GUID;
     EFI_STATUS Status;
 
     /* Open the XTLDR protocol */