This fixes a rendering issue (and ultimately a crash) in PowerPoint when
compiling with GCC 8.
GCC8 doesn't support the `excess-precision=standard` option under the
`#pragma GCC optimize` directive.
This results in unpredictable floating point rounding leading to errors
when inserting segments (with missing edges and/or triangles).
Using 24-bit precision ensures we don't have any excess precision.
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v4: d2d1: Fix double free bug when d2d_geometry_sink_Close fails
d2d1: Use 24-bit FP precision for triangulate.
https://gitlab.winehq.org/wine/wine/-/merge_requests/4824