MdeModulePkg: PeiMain: Updated dispatcher for delayed dispatch

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4496

This change adds a check for PEI dispatcher to continue dispatching when
there are still pending delayed dispatch requests, to be compatible with
newly integrated Delayed Dispatcher PPI interface.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Debkumar De <debkumar.de@intel.com>
Cc: Catharine West <catharine.west@intel.com>

Co-authored-by: John Schock <joschock@microsoft.com>
Signed-off-by: Kun Qin <kuqin12@gmail.com>

MdeModulePkg/Core/Pei/Dispatcher/Dispatcher.c

@@ -2108,7 +2108,10 @@ PeiDispatcher (
     //  pass. If we did not dispatch a PEIM/FV there is no point in trying again
     //  as it will fail the next time too (nothing has changed).
     //
-  } while (Private->PeimNeedingDispatch && Private->PeimDispatchOnThisPass);
+    // Also continue dispatch loop if there are outstanding delay-
+    // dispatch registrations still running.
+  } while ((Private->PeimNeedingDispatch && Private->PeimDispatchOnThisPass) ||
+           (Private->DelayedDispatchTable->Count > 0));
 }
 
 /**