scanner: Fix unregistering of the timeout callback
scanner: Fix unregistering of the timeout callback

ali/mopidy,vrs01/mopidy,rawdlite/mopidy,bencevans/mopidy,ZenithDK/mopidy,adamcik/mopidy,jmarsik/mopidy,bencevans/mopidy,glogiotatidis/mopidy,swak/mopidy,glogiotatidis/mopidy,pacificIT/mopidy,quartz55/mopidy,jodal/mopidy,vrs01/mopidy,mokieyue/mopidy,swak/mopidy,quartz55/mopidy,ali/mopidy,hkariti/mopidy,ali/mopidy,jodal/mopidy,ZenithDK/mopidy,SuperStarPL/mopidy,ZenithDK/mopidy,kingosticks/mopidy,tkem/mopidy,bencevans/mopidy,pacificIT/mopidy,ZenithDK/mopidy,swak/mopidy,hkariti/mopidy,bacontext/mopidy,woutervanwijk/mopidy,priestd09/mopidy,abarisain/mopidy,pacificIT/mopidy,mokieyue/mopidy,jcass77/mopidy,quartz55/mopidy,SuperStarPL/mopidy,rawdlite/mopidy,jmarsik/mopidy,priestd09/mopidy,SuperStarPL/mopidy,bacontext/mopidy,pacificIT/mopidy,mokieyue/mopidy,jmarsik/mopidy,mopidy/mopidy,vrs01/mopidy,dbrgn/mopidy,bacontext/mopidy,jmarsik/mopidy,jcass77/mopidy,kingosticks/mopidy,liamw9534/mopidy,adamcik/mopidy,diandiankan/mopidy,kingosticks/mopidy,bacontext/mopidy,tkem/mopidy,SuperStarPL/mopidy,bencevans/mopidy,diandiankan/mopidy,swak/mopidy,jodal/mopidy,glogiotatidis/mopidy,liamw9534/mopidy,glogiotatidis/mopidy,tkem/mopidy,hkariti/mopidy,adamcik/mopidy,mopidy/mopidy,woutervanwijk/mopidy,ali/mopidy,mopidy/mopidy,jcass77/mopidy,hkariti/mopidy,dbrgn/mopidy,diandiankan/mopidy,priestd09/mopidy,diandiankan/mopidy,dbrgn/mopidy,abarisain/mopidy,tkem/mopidy,rawdlite/mopidy,quartz55/mopidy,mokieyue/mopidy,dbrgn/mopidy,rawdlite/mopidy,vrs01/mopidy