Fix luminanceReduction shader name

Author: VReaperV

src/engine/renderer/glsl_source/luminanceReduction_cp.glsl

@@ -32,7 +32,7 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
 
-/* adaptiveLightingReduction_cp.glsl */
+/* luminanceReduction_cp.glsl */
 
 #insert common_cp