sys/log: Call registered handler for slot1 sub-logs
sys/log: Call registered handler for slot1 sub-logs

Once we switch slot1 to one of sub-logs (FCB or CBMEM) we should call
also registered handler for new active log to make sure it is
initialized properly.

mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core