fix another test for miri

Author: workingjubilee

tests/smoke.rs

@@ -289,9 +289,9 @@ fn sp_smoke_test() {
                         })
             });
 
-            let sp = frame.sp() as usize;
-            eprintln!("sp  = {:p}", sp as *const u8);
-            if sp == 0 {
+            let sp = frame.sp();
+            eprintln!("sp  = {sp:p}");
+            if sp as usize == 0 {
                 // If the SP is null, then we don't have an implementation for
                 // getting the SP on this target. Just keep walking the stack,
                 // but don't make our assertions about the on-stack pointers and