This fixes https://bugs.winehq.org/show_bug.cgi?id=52094.
-- v8: ntdll: Properly track refcount with forwarded exports. ntdll: Don't re-add a module dependency if it already exists. ntdll: Remove some unnecessary NULL checks for current_importer. ntdll: Set export forwarder DLL as the dynamic importer in LdrGetProcedureAddress(). ntdll: Wrap current_modref variable in a new structure.