Callback: Deprecated attach member function in favor of simple assignment
Callback: Deprecated attach member function in favor of simple assignment

The attach function is used several other places to indicate
registration for interrupts. This differs significantly to its use in
the Callback class. Additionally, the attach function is unnecessary
given that simple assignment works just as well.

fanghuaqi/mbed,catiedev/mbed-os,YarivCol/mbed-os,NXPmicro/mbed,monkiineko/mbed-os,radhika-raghavendran/mbed-os5.1-onsemi,YarivCol/mbed-os,mazimkhan/mbed-os,RonEld/mbed,bcostm/mbed-os,nRFMesh/mbed-os,RonEld/mbed,karsev/mbed-os,mmorenobarm/mbed-os,adustm/mbed,CalSol/mbed,fanghuaqi/mbed,RonEld/mbed,adamgreen/mbed,kl-cruz/mbed-os,radhika-raghavendran/mbed-os5.1-onsemi,arostm/mbed-os,CalSol/mbed,netzimme/mbed-os,cvtsi2sd/mbed-os,fahhem/mbed-os,catiedev/mbed-os,CalSol/mbed,karsev/mbed-os,svogl/mbed-os,fahhem/mbed-os,catiedev/mbed-os,radhika-raghavendran/mbed-os5.1-onsemi,nvlsianpu/mbed,ryankurte/mbed-os,mikaleppanen/mbed-os,betzw/mbed-os,mbedmicro/mbed,nvlsianpu/mbed,ryankurte/mbed-os,NXPmicro/mbed,bulislaw/mbed-os,bcostm/mbed-os,theotherjimmy/mbed,theotherjimmy/mbed,j-greffe/mbed-os,kjbracey-arm/mbed,CalSol/mbed,ryankurte/mbed-os,RonEld/mbed,bulislaw/mbed-os,cvtsi2sd/mbed-os,infinnovation/mbed-os,mikaleppanen/mbed-os,mbedmicro/mbed,catiedev/mbed-os,andcor02/mbed-os,HeadsUpDisplayInc/mbed,NXPmicro/mbed,theotherjimmy/mbed,mbedmicro/mbed,YarivCol/mbed-os,karsev/mbed-os,nRFMesh/mbed-os,netzimme/mbed-os,monkiineko/mbed-os,svogl/mbed-os,j-greffe/mbed-os,arostm/mbed-os,kjbracey-arm/mbed,betzw/mbed-os,c1728p9/mbed-os,c1728p9/mbed-os,RonEld/mbed,betzw/mbed-os,bulislaw/mbed-os,catiedev/mbed-os,andcor02/mbed-os,mikaleppanen/mbed-os,kl-cruz/mbed-os,fahhem/mbed-os,CalSol/mbed,bcostm/mbed-os,karsev/mbed-os,andcor02/mbed-os,Archcady/mbed-os,betzw/mbed-os,fahhem/mbed-os,kl-cruz/mbed-os,cvtsi2sd/mbed-os,nRFMesh/mbed-os,radhika-raghavendran/mbed-os5.1-onsemi,HeadsUpDisplayInc/mbed,mmorenobarm/mbed-os,nRFMesh/mbed-os,infinnovation/mbed-os,mikaleppanen/mbed-os,mmorenobarm/mbed-os,j-greffe/mbed-os,c1728p9/mbed-os,screamerbg/mbed,kl-cruz/mbed-os,bulislaw/mbed-os,radhika-raghavendran/mbed-os5.1-onsemi,arostm/mbed-os,pradeep-gr/mbed-os5-onsemi,netzimme/mbed-os,mazimkhan/mbed-os,kjbracey-arm/mbed,andcor02/mbed-os,adamgreen/mbed,monkiineko/mbed-os,mmorenobarm/mbed-os,infinnovation/mbed-os,betzw/mbed-os,mmorenobarm/mbed-os,screamerbg/mbed,monkiineko/mbed-os,j-greffe/mbed-os,screamerbg/mbed,pradeep-gr/mbed-os5-onsemi,adustm/mbed,NXPmicro/mbed,bulislaw/mbed-os,pradeep-gr/mbed-os5-onsemi,mbedmicro/mbed,kl-cruz/mbed-os,adustm/mbed,infinnovation/mbed-os,kjbracey-arm/mbed,svogl/mbed-os,mikaleppanen/mbed-os,svogl/mbed-os,mmorenobarm/mbed-os,bulislaw/mbed-os,andcor02/mbed-os,netzimme/mbed-os,theotherjimmy/mbed,ryankurte/mbed-os,Archcady/mbed-os,c1728p9/mbed-os,andcor02/mbed-os,Archcady/mbed-os,cvtsi2sd/mbed-os,NXPmicro/mbed,mazimkhan/mbed-os,ryankurte/mbed-os,YarivCol/mbed-os,NXPmicro/mbed,monkiineko/mbed-os,bcostm/mbed-os,nRFMesh/mbed-os,screamerbg/mbed,theotherjimmy/mbed,adamgreen/mbed,svogl/mbed-os,pradeep-gr/mbed-os5-onsemi,fanghuaqi/mbed,betzw/mbed-os,RonEld/mbed,adamgreen/mbed,mazimkhan/mbed-os,monkiineko/mbed-os,HeadsUpDisplayInc/mbed,adamgreen/mbed,mbedmicro/mbed,arostm/mbed-os,mazimkhan/mbed-os,c1728p9/mbed-os,HeadsUpDisplayInc/mbed,pradeep-gr/mbed-os5-onsemi,svogl/mbed-os,adustm/mbed,Archcady/mbed-os,fanghuaqi/mbed,bcostm/mbed-os,mikaleppanen/mbed-os,nvlsianpu/mbed,YarivCol/mbed-os,CalSol/mbed,adustm/mbed,fanghuaqi/mbed,nvlsianpu/mbed,HeadsUpDisplayInc/mbed,arostm/mbed-os,pradeep-gr/mbed-os5-onsemi,fahhem/mbed-os,j-greffe/mbed-os,netzimme/mbed-os,HeadsUpDisplayInc/mbed,bcostm/mbed-os,nvlsianpu/mbed,screamerbg/mbed,Archcady/mbed-os,c1728p9/mbed-os,fahhem/mbed-os,j-greffe/mbed-os,arostm/mbed-os,infinnovation/mbed-os,karsev/mbed-os,nRFMesh/mbed-os,ryankurte/mbed-os,adustm/mbed,cvtsi2sd/mbed-os,nvlsianpu/mbed,infinnovation/mbed-os,screamerbg/mbed,radhika-raghavendran/mbed-os5.1-onsemi,karsev/mbed-os,theotherjimmy/mbed,catiedev/mbed-os,YarivCol/mbed-os,adamgreen/mbed,cvtsi2sd/mbed-os,netzimme/mbed-os,mazimkhan/mbed-os,kl-cruz/mbed-os,Archcady/mbed-os