MinGW doesn't support _create_locale or _free_locale

MinGW has limited support for locale-specific functionality used in the recently merged OCCT 6.6.0
MinGW doesn't support the locale functionality that MSVC does

MinGW has limited support for locale-specific functionality used in the recently merged OCCT 6.6.0
MinGW doesn't support locale-specific I/O functions

MinGW has limited support for locale-specific functionality used in the recently merged OCCT 6.6.0
Merge pull request #405 from tpaviot/review/MinGWLocaleFixes

Fix locale-related errors for MinGW