This makes the emulator suitable to run the base SMS recipe.
It seems to be picky about where it accepts its link flags.
VDP kinda works. Can see the Collapse OS prompt with SMS base recipe if `STDIO_GETC` gets replaced with infinite loop (no input emul yet).
I implement the screen using XCB which is much more friendly than z80e's SDL+CMake for development machines that want to install minimal dependencies (for example, a port-less OpenBSD rig).