43e17454e2
Its usage was removed in 5e624bf4ba and 093b075d32, so we do not need to keep it around any longer. According to [preliminary input](https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/Find.20.60rustc_driver.60.20dependent.20projects.3F/near/304490764), we do not need to worry about any deprecation cycle for this API and can just straight up remove it. Migration instructions for remaining clients -------------------------------------------- Change from ```rust extern crate rustc_driver; fn main() { rustc_driver::set_sigpipe_handler(); // ... ``` to ```rust fn main() { // ... ```