Update src/bootstrap/src/lib.rs

Co-authored-by: Urgau <3616612+Urgau@users.noreply.github.com>

Author: SchmErik

src/bootstrap/src/lib.rs

@@ -98,6 +98,7 @@ const EXTRA_CHECK_CFGS: &[(Option<Mode>, &str, Option<&[&'static str]>)] = &[
     /* Extra values not defined in the built-in targets yet, but used in std */
     (Some(Mode::Std), "target_env", Some(&["libnx"])),
     // (Some(Mode::Std), "target_os", Some(&[])),
+    // #[cfg(bootstrap)] zkvm
     (Some(Mode::Std), "target_os", Some(&["zkvm"])),
     (Some(Mode::Std), "target_vendor", Some(&["risc0"])),
     (Some(Mode::Std), "target_arch", Some(&["asmjs", "spirv", "nvptx", "xtensa"])),