Revert "Don't use StringFormat::GenericTypographic() in MSW wxGraphicsContext."

Revert "Don't use StringFormat::GenericTypographic() in MSW wxGraphicsContext."

This reverts r72442 and restores the use of GenericTypographic string format
for GDI+ text rendering. While it's true that using this flag with small font
sizes results in pretty bad output, especially under Windows XP, not using it
results in wrong text extent calculations for all sizes which is even worse.

See #14537.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72583 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775