Ensure configure.rs changes trigger rebuilds

Author: tgross35

crates/compiler-builtins-smoke-test/build.rs

@@ -2,6 +2,7 @@
 mod configure;
 
 fn main() {
+    println!("cargo:rerun-if-changed=../../configure.rs");
     let cfg = configure::Config::from_env();
     configure::emit_libm_config(&cfg);
 }

crates/libm-test/build.rs

@@ -3,6 +3,7 @@ mod configure;
 use configure::Config;
 
 fn main() {
+    println!("cargo:rerun-if-changed=../../configure.rs");
     let cfg = Config::from_env();
     configure::emit_test_config(&cfg);
 }

crates/util/build.rs

@@ -4,6 +4,7 @@
 mod configure;
 
 fn main() {
+    println!("cargo:rerun-if-changed=../../configure.rs");
     let cfg = configure::Config::from_env();
     configure::emit_libm_config(&cfg);
 }