ntdll: Properly track refcount with forwarded exports.
This fixes https://bugs.winehq.org/show_bug.cgi?id=52094.
For reference, here's how current_modref is being passed around (before this patch):
graph TB
fii["fixup_imports_ilonly<br><em style='color:#ff0'>(directly sets current_modref)</em>"]
fi["fixup_imports<br><em style='color:#ff0'>(directly sets current_modref)</em>"]
pa["process_attach<br><em style='color:#ff0'>(directly sets current_modref)</em>"]
ld[load_dll]
id["import_dll<br><em style='color:#0f0'>(directly uses current_modref)</em>"]
bin["build_import_name<br><em style='color:#0f0'>(directly uses current_modref)</em>"]
foe["find_ordinal_export<br><em style='color:#0f0'>(uses current_modref for relay)</em>"]
ffe["find_forwarded_export<br><em style='color:#0f0'>(directly uses current_modref)</em>"]
fne[find_named_export]
MI[MODULE_InitDLL]
fii --> ld
fi --> id
pa --> MI -.-> DllMain
id --> bin
id --> ld
id --> foe
id --> fne --> foe --> ffe --> foe
ffe --> fne
ffe --> bin
style DllMain color:red;
Edited by Jinoh Kang