EDataCal: Remove OP_SET_BACKEND_PROPERTY.
EDataCal: Remove OP_SET_BACKEND_PROPERTY.

No longer used.

Distrotech/evolution-data-server,matzipan/evolution-data-server,Distrotech/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,Distrotech/evolution-data-server,Distrotech/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server,Distrotech/evolution-data-server,tintou/evolution-data-server,tintou/evolution-data-server