remove duplicate check

Author: yerke

src/cargo/core/compiler/build_config.rs

@@ -63,9 +63,6 @@ impl BuildConfig {
     ) -> CargoResult<BuildConfig> {
         let cfg = config.build_config()?;
         let requested_kinds = CompileKind::from_requested_targets(config, requested_targets)?;
-        if jobs == Some(0) {
-            anyhow::bail!("jobs may not be 0")
-        }
         if jobs.is_some() && config.jobserver_from_env().is_some() {
             config.shell().warn(
                 "a `-j` argument was passed to Cargo but Cargo is \