Rollup merge of rust-lang#77146 - Mark-Simulacrum:xpyinstall, r=alexcrichton

Install std for non-host targets

It seems reasonable that when configuring various targets you'd expect all of them to get std installed, even if you're not building compiler toolchains for each of those.

cc rust-lang#76990

r? @alexcrichton

Author: jonas-schievink

src/bootstrap/install.rs

@@ -192,7 +192,7 @@ install!((self, builder, _config),
         builder.ensure(dist::Docs { host: self.target });
         install_docs(builder, self.compiler.stage, self.target);
     };
-    Std, "library/std", true, only_hosts: true, {
+    Std, "library/std", true, only_hosts: false, {
         for target in &builder.targets {
             builder.ensure(dist::Std {
                 compiler: self.compiler,