fix: optimization: PVS-Studio warning V813

Passing large objects by const reference avoids unnecessary copying and enhances efficiency.

Reported by: PVS-Studio
Signed-off-by: Vyacheslav Ivanov <islavaivanov76@gmail.com>

src/audio/AL/alutil.hpp

@@ -40,7 +40,8 @@ namespace AL {
     /// @param field enum value
     /// @param def default value will be returned in case of error
     /// @return field value or default
-    inline glm::vec3 getSource3f(uint source, ALenum field, glm::vec3 def={}) {
+    inline glm::vec3 getSource3f(uint source, ALenum field, const glm::vec3& def= {}
+    ) {
         glm::vec3 value = def;
         if (source == 0)
             return def;