This PR adds support to the cmake build scripts so to allow building SDL with the Tiny C Compiler (tcc).
TinyCC supports the subset of C99 used by SDL and will complete the build once the --version-script linker flag is removed. The changes have been tested with various build configurations, including X11 and Wayland, and using tcc version 0.9.28rc 2025-10-27 mob@f4e01bfc on x86_64 Linux.