Added a missing backtick to no std

MagnumOpus21 · Siva Prasad · commit 5e7039411b08 · 2018-09-05T08:56:00.000-04:00
diff --git a/src/libcore/macros.rs b/src/libcore/macros.rs
@@ -350,7 +350,7 @@ macro_rules! try {
 /// assert_eq!(v, b"s = \"abc 123\"");
 /// ```
 ///
-/// Note: This macro can be used in no_std setups as well
+/// Note: This macro can be used in `no_std` setups as well
 /// In a `no_std` setup you are responsible for the
 /// implementation details of the components.
 ///
