Add regression test for issue-77475

Author: JohnTitor

src/test/ui/macros/issue-77475.rs

@@ -0,0 +1,10 @@
+// check-pass
+// Regression test of #77475, this used to be ICE.
+
+#![feature(decl_macro)]
+
+use crate as _;
+
+pub macro ice(){}
+
+fn main() {}