Apple build fix

src/disk/zip.c

@@ -821,7 +821,9 @@ zip_update_request_length(zip_t *dev, int len, int block_len)
                     break;
                 }
             }
+#ifndef __APPLE__
             [[fallthrough]];
+#endif
 
         default:
             dev->packet_len = len;
@@ -1409,7 +1411,9 @@ zip_command(scsi_common_t *sc, uint8_t *cdb)
                 zip_invalid_field(dev);
                 return;
             }
+#ifndef __APPLE__
             [[fallthrough]];
+#endif
         case GPCMD_SCSI_RESERVE:
         case GPCMD_SCSI_RELEASE:
         case GPCMD_TEST_UNIT_READY:
@@ -1572,7 +1576,9 @@ zip_command(scsi_common_t *sc, uint8_t *cdb)
                 zip_command_complete(dev);
                 break;
             }
+#ifndef __APPLE__
             [[fallthrough]];
+#endif
         case GPCMD_WRITE_6:
         case GPCMD_WRITE_10:
         case GPCMD_WRITE_AND_VERIFY_10: