Rollup merge of rust-lang#40453 - tschottdorf:lint-deny-wording, r=al…

…excrichton

Improve wording in the -{W,A,F,D} options

This was so trivial that I'm wondering whether I'm missing something.

Fixes rust-lang#28708.

src/librustc_driver/lib.rs

@@ -738,7 +738,7 @@ Available lint options:
               Allow <foo>
     -D <foo>           Deny <foo>
     -F <foo>           Forbid <foo> \
-              (deny, and deny all overrides)
+              (deny <foo> and all attempts to override)
 
 ");