Supress return_address test on miri

Author: chorman0773

library/core/src/arch.rs

@@ -94,6 +94,7 @@ pub fn breakpoint() {
 ///
 /// ## Example
 /// ```
+/// # #![cfg(not(miri))] // FIXME: Figure out how to make miri work before stabilizing this macro
 /// #![feature(return_address)]
 ///
 /// let addr = core::arch::return_address!();