Update the logic for action opcode, also support user input a empty string for QuestionConfig part.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17189 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/SetupBrowserDxe/Presentation.c

@@ -1426,6 +1426,8 @@ ProcessQuestionConfig (
   ConfigResp = GetToken (Question->QuestionConfig, Selection->FormSet->HiiHandle);
   if (ConfigResp == NULL) {
     return EFI_NOT_FOUND;
+  } else if (ConfigResp[0] == L'\0') {
+    return EFI_SUCCESS;
   }
 
   //