Fix some Lintian warnings

Don't package .so library, fix Lintian warning link-to-shared-library-in-wrong-package

Update soname in override, fix Lintian warning mismatched-override

I've updated the source upstream to move the remaining files from Latin1 encoding to UTF-8. The related warnings will thus disappear with the next upstream version.

About this MR, I think the .so file is only necessary when compiling something on top of V_Sim, but since we're not providing any header files, there is no need to include it in the main executable package. I've compiled new packages locally on my device and they seem to work properly without the .so link. About extending V_Sim, there already is the gobject-introspection stuff that provides this capability. In case someone would like to develop a C or C++ plugin, we can still include later a -dev package with the headers and the .so. I think for the moment we're fine without. Do you agree ?