config: Fix bitwise copy-and-pasto for command line items.

The recent change allowing every configuration option to appear on the
command line wrongly used bitwise AND to set a flag.  This patch fixes
the bug by using the proper bitwise OR idiom.

Signed-off-by: Richard Cochran <[email protected]>
Reported-by: Miroslav Lichvar <[email protected]>
Fixes: 4e8dbd8 ("ptp4l: Accept any configuration option as a command line argument.")

config.c

@@ -418,7 +418,7 @@ static enum parser_result parse_item(struct config *cfg,
 	}
 
 	if (commandline) {
-		dst->flags &= CFG_ITEM_LOCKED;
+		dst->flags |= CFG_ITEM_LOCKED;
 	}
 	return PARSED_OK;
 }