rz-mux-tool.sh: do not default to 'error' log level
rz-mux-tool.sh: do not default to 'error' log level

yuvadm/rhizi,Rhizi/rhizi,tlevine/rhizi,ozFri/rhizi,shlomif/rhizi,cben/rhizi,tlevine/rhizi,Rhizi/rhizi,Rhizi/rhizi,Rhizi/rhizi,yuvadm/rhizi,cben/rhizi,ozFri/rhizi,cben/rhizi,shlomif/rhizi,cben/rhizi,yuvadm/rhizi,shlomif/rhizi,tlevine/rhizi,shlomif/rhizi,yuvadm/rhizi,ozFri/rhizi,ozFri/rhizi,tlevine/rhizi