[Bug 46180] wineserver does not release atom on unregistering window classes

https://bugs.winehq.org/show_bug.cgi?id=46180

--- Comment #8 from Ralf Habacker  ---
I filed two patches:

1. a related test https://source.winehq.org/patches/data/154951 and 
2. the main patch https://source.winehq.org/patches/data/154952

Please note that without patch 2, patch 1 will not run successful, but
submitting guide mentions to provide test patch first.