libedit

• musl defines __STDC_ISO_10646__ in stdc-predef.h which gets included by gcc by default (unlike clang)
• readline/history.h and readline/tilde.h can be symlinked to editline/readline.h
• Prefer symlinks to libedit.so instead of linker scripts INPUT(-ledit)

References

• https://github.com/chimera-linux/cports/blob/master/main/libedit
• https://github.com/chimera-linux/libedit-chimera
• https://github.com/sabotage-linux/sabotage/blob/master/pkg/libedit