pkgconfig file on Windows seems broken

We are currently patching the pkgconfig file for Windows. https://github.com/conda-forge/libode-feedstock/blob/master/recipe/modify-dotpc-win.patch We use a `-I:{includedir}` syntax that accidentally adds an extra `:` at the front of the path. These pkgconfig files are also read by e.g. CMake which is where this breaks (in OMPL).

I wonder if hte following patch would be better?

@traversaro maybe you know if this would work on Windows?

```patch
Index: ode-0.16/ode.pc.in
===================================================================
--- ode-0.16.orig/ode.pc.in
+++ ode-0.16/ode.pc.in
@@ -7,6 +7,6 @@ precision=@ODE_PRECISION@
Name: ode
Description: Open Dynamics Engine
Version: @ODE_VERSION@
-Libs: -L${libdir} -lode
-Libs.private: -lstdc++ -lm
-Cflags: -I${includedir}
+Libs: -L${libdir} -lode_double
+# Libs.private: -lstdc++ -lm
+Cflags: -I${includedir}
```

cc @johnwason

Start by reviewing recipe/modify-dotpc-win.patch and the proposed ode.pc.in changes, then check how the generated pkgconfig file is consumed by CMake on Windows. Verify the include and library flags, including the ODE library name, and confirm that the resulting file works for the OMPL use case.

Written by the indexing model from the issue text.