Update ldrdllnotification.md

[RatinCN]

• Add missing PCLDR_DLL_NOTIFICATION_DATA type definition, which is presenting in LdrDllNotification declaration in Syntax section:

VOID CALLBACK LdrDllNotification(
  _In_     ULONG                       NotificationReason,
  _In_     PCLDR_DLL_NOTIFICATION_DATA NotificationData,
  _In_opt_ PVOID                       Context
);

• The programming language used in sample code fragment should be C++

[prmerger-automator]

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