Add and use more static symbols.

Note that the output of `unpretty-debug.stdout` has changed. In that
test the hash values are normalized from a symbol numbers to small
numbers like "0#0" and "0#1". The increase in the number of static
symbols must have caused the original numbers to contain more digits,
resulting in different pretty-printing prior to normalization.

src/librustc_interface/util.rs

@@ -53,7 +53,7 @@ pub fn add_configuration(
     cfg.extend(target_features.into_iter().map(|feat| (tf, Some(feat))));
 
     if sess.crt_static(None) {
-        cfg.insert((tf, Some(Symbol::intern("crt-static"))));
+        cfg.insert((tf, Some(sym::crt_dash_static)));
     }
 }