Remove manual '--target'

Author: Aaron1011

src/bin/cargo-miri.rs

@@ -502,7 +502,6 @@ fn in_cargo_miri() {
         // this target.  The user gets to control what gets actually passed to Miri.
         let mut cmd = cargo();
         cmd.arg("check");
-        cmd.arg("--target").arg("x86_64-unknown-linux-gnu");
         match (subcommand, kind.as_str()) {
             (MiriCommand::Run, "bin") => {
                 // FIXME: we just run all the binaries here.