Use simpler #[cfg(windows)]

Author: princh-asger

crates/libs/core/src/strings/pcwstr.rs

@@ -32,15 +32,15 @@ impl PCWSTR {
     ///
     /// The `PCWSTR`'s pointer needs to be valid for reads up until and including the next `\0`.
     pub unsafe fn len(&self) -> usize {
-        #[cfg(target_os = "windows")]
+        #[cfg(windows)]
         let len = {
             extern "C" {
                 fn wcslen(s: *const u16) -> usize;
             }
             wcslen(self.0)
         };
 
-        #[cfg(not(target_os = "windows"))]
+        #[cfg(not(windows))]
         let len = {
             let mut len = 0;
             let mut ptr = self.0;