Re-add track_caller to panic_no_unwind in bootstrap

This function was updated in a recent PR (92911) to be called without the caller
information passed in, but the function signature itself was not altered with
cfg_attr at the time.

Author: Mark-Simulacrum

library/core/src/panicking.rs

@@ -84,8 +84,11 @@ fn panic_bounds_check(index: usize, len: usize) -> ! {
     panic!("index out of bounds: the len is {} but the index is {}", len, index)
 }
 
+// This function is called directly by the codegen backend, and must not have
+// any extra arguments (including those synthesized by track_caller).
 #[cold]
 #[inline(never)]
+#[cfg_attr(bootstrap, track_caller)]
 #[lang = "panic_no_unwind"] // needed by codegen for panic in nounwind function
 fn panic_no_unwind() -> ! {
     if cfg!(feature = "panic_immediate_abort") {