libmpdclient: reset "receiving" on error
libmpdclient: reset "receiving" on error

The "receiving" flag must be reset when an error occurs.  If not, the
function mpd_finishCommand() goes into an endless loop.

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