dumpcpp tool not working for x64 components

Given a registered x64 ActiveX control

When I run `dumpcpp "{CLSID}" on the command line

Then an error with message "dumpcpp: type library '' not found" is displayed.

However, it works with x86 versions of the active controls and the tools dumpdoc and testcon have no problems with the x64 version.

After looking at the source code (dumpcpp/main.cpp) this is due to a hard coded "win32" registry subkey at two different places. 64-bit controls are however registered with a "win64" subkey. Changing "win32" to "win64" works.

This problem might affect multiple versions of Qt.