Previously, wmmixer-alsa existed as an object in the repository named
wmmixer-alsa-0.6. However, it was not a directory and contained no files.
This patch removes this object and adds the source to wmmixer-alsa. It was
obtained by extracting wmmixer-alsa-0.6.tar.gz from the source rpm found at
http://ftp.cc.uoc.gr/mirrors/linux/pld/pool/w/wmmixer-alsa/.