Style: Replace header guards with #pragma once

platform/windows/wgl_detect_version.h

@@ -28,8 +28,7 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#ifndef WGL_DETECT_VERSION_H
-#define WGL_DETECT_VERSION_H
+#pragma once
 
 #if defined(WINDOWS_ENABLED) && defined(GLES3_ENABLED)
 
@@ -38,5 +37,3 @@ class Dictionary;
 Dictionary detect_wgl();
 
 #endif // WINDOWS_ENABLED && GLES3_ENABLED
-
-#endif // WGL_DETECT_VERSION_H