Rollup merge of #118993 - jyn514:cfg-color, r=WaffleLapkin,Nilstrieb

use `if cfg!` instead of `#[cfg]`

this pr is specifically for waffle because i love it <3

fixes #118756 (comment)

r? `@WaffleLapkin`

Author: workingjubilee

compiler/rustc_errors/src/emitter.rs

@@ -2677,10 +2677,7 @@ fn from_stderr(color: ColorConfig) -> Destination {
 /// On Windows, BRIGHT_BLUE is hard to read on black. Use cyan instead.
 ///
 /// See #36178.
-#[cfg(windows)]
-const BRIGHT_BLUE: Color = Color::Cyan;
-#[cfg(not(windows))]
-const BRIGHT_BLUE: Color = Color::Blue;
+const BRIGHT_BLUE: Color = if cfg!(windows) { Color::Cyan } else { Color::Blue };
 
 impl Style {
     fn color_spec(&self, lvl: Level) -> ColorSpec {