Fixed warnings.

src/image_decode.cpp

@@ -140,6 +140,9 @@ namespace bimg
 							palette = true;
 							supported = true;
 							break;
+
+						case LCT_MAX_OCTET_VALUE:
+							break;
 					}
 					break;
 
@@ -194,6 +197,9 @@ namespace bimg
 
 						case LCT_PALETTE:
 							break;
+
+						case LCT_MAX_OCTET_VALUE:
+							break;
 					}
 					break;
 
@@ -371,6 +377,9 @@ namespace bimg
 					case LCT_PALETTE:
 						output->m_hasAlpha = lodepng_has_palette_alpha(&state.info_raw);
 						break;
+
+					case LCT_MAX_OCTET_VALUE:
+						break;
 				}
 			}
 			else