This fixes https://bugs.winehq.org/show_bug.cgi?id=52094.
-- v2: ntdll: Properly track refcount with forwarded exports. ntdll: Update current_modref in LdrGetProcedureAddress(). ntdll: De-duplicate module dependency edges. ntdll: Introduce struct dependency_edge as wrapper around LDR_DEPENDENCY. kernel32/tests: Test module refcounting with forwarded exports.