Simplified call to platform-specific extension check.

src/opengl.c

@@ -639,11 +639,8 @@ GLFWAPI int glfwExtensionSupported(const char* extension)
         }
     }
 
-    // Additional platform specific extension checking (e.g. WGL)
+    // Check if extension is in the platform-specific string
-    if (_glfwPlatformExtensionSupported(extension))
+    return _glfwPlatformExtensionSupported(extension);
-        return GL_TRUE;
-
-    return GL_FALSE;
 }