Bug on predefined Macros that are INTEGER_LITERAL

[trolldbois]

2021-03 Both compiler's Predefined Macros and standard's Preprocessor Macros handling works for string values. But predef macros for INTEGER_LITERAL do NOT work. From MACRO_DEFINITION

See https://github.com/trolldbois/ctypeslib/ctypeslib/codegen/cursorhandler.py#L451 in literal_handling. No tokens are available for INTEGER_LITERAL. Where we just use spelling for STRING_LITERAL

https://gcc.gnu.org/onlinedocs/cpp/Standard-Predefined-Macros.html
https://blog.kowalczyk.info/article/j/guide-to-predefined-macros-in-c-compilers-gcc-clang-msvc-etc..html