Add sample code for EFI_IFR_QUESTION_REF3 opcode.

Signed-off-by: ydong10
Reviewed-by: lgao4

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12783 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/DriverSampleDxe/DriverSample.c

@@ -1909,6 +1909,14 @@ DriverSampleInit (
 
   PrivateData->HiiHandle[1] = HiiHandle[1];
 
+  //
+  // Update the device path string.
+  //
+  if (HiiSetString (HiiHandle[0], STRING_TOKEN (STR_DEVICE_PATH), (EFI_STRING) &mHiiVendorDevicePath0, NULL) == 0) {
+    DriverSampleUnload (ImageHandle);
+    return EFI_OUT_OF_RESOURCES;
+  }
+  
   //
   // Very simple example of how one would update a string that is already
   // in the HII database

MdeModulePkg/Universal/DriverSampleDxe/Vfr.vfr

@@ -320,7 +320,7 @@ formset
             minimum = 0,
             maximum = 0xf0,
             step    = 0,
-            default = 21,
+            default value = questionrefval(devicepath = STRING_TOKEN (STR_DEVICE_PATH), guid = DRIVER_SAMPLE_FORMSET_GUID, 0x1111),
 
             inconsistentif prompt = STRING_TOKEN(STR_ERROR_POPUP),
               ideqval MyIfrNVData.HowOldAreYouInYearsManual == 99