set of windows (mingw64) build fixes

[w0lek]

There are a couple compilation fixes for mingw64 build

Description

Two kind of changes:

1. removed unused function

char* getline(char*& _lineptr, FILE* _stream)

This function has compilation issue and is not actually used and looks obsolete.
If removing is not an option, i will think how to correct code without removing it.

2. #define _USE_MATH_DEFINES for _WIN32 platform to ensure (non-standard) value of M_PI is brought in from math.h

Related Issue

#3076

Motivation and Context

Allows to build application on windows platform using mingw64

How Has This Been Tested?

It was tested as a part of hotfixes for a several releases in Aurora package (windows build)

Types of changes

• Compilation errors
• Bug fix (change which fixes an issue)
• New feature (change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• All new and existing tests passed

[AmirhosseinPoolad]

Thanks for the PR @w0lek. regarding the getline function, even if it wasn't unused I fully support removing it. Seems like a relic from the old C days.

Other than that I had a suggestion on a way to avoid ifdefs for windows compatibility.

[vaughnbetz]

Suggest just using std::math::pi instead of bringing in the _USE_MATH_DEFINES

[w0lek]

Suggest just using std::math::pi instead of bringing in the _USE_MATH_DEFINES

done

[AlexandreSinger]

LGTM