fixed missing comma in tag.c
fixed missing comma in tag.c

yusiwen/libmpdclient,jagleeso/libmpdclient,jagleeso/libmpdclient,yusiwen/libmpdclient,yusiwen/libmpdclient,jagleeso/libmpdclient,cmende/libmpdclient,OpenInkpot-archive/iplinux-libmpdclient,sl0th/libmpdclient,sl0th/libmpdclient,OpenInkpot-archive/iplinux-libmpdclient,jwise/libmpdclient,jwise/libmpdclient,jwise/libmpdclient,psych0tik/libmpdclient2,cmende/libmpdclient,cmende/libmpdclient,sl0th/libmpdclient,psych0tik/libmpdclient2