controller: datastore: clean up CNCI channel handling
controller: datastore: clean up CNCI channel handling

Make sure to lock the channel map before checking it.  Also
delete the map entry rather than simply setting it to nil.

Signed-off-by: Kristen Carlson Accardi <047ff8258f0113ece56e5e2fe9e0d987b14c4333@linux.intel.com>

chavafg/ciao,rbradford/ciao,mrkz/ciao,kaccardi/ciao,jorgevgut/ciao,rbradford/ciao,mcastelino/ciao,tpepper/ciao,markdryan/ciao,kaccardi/ciao,jorgevgut/ciao,01org/ciao,01org/ciao,leoswaldo/ciao,wcwxyz/ciao,mcastelino/ciao,obedmr/ciao,leoswaldo/ciao,markdryan/ciao,mrkz/ciao,tpepper/ciao,jorgevgut/ciao,obedmr/ciao,erick0z/ciao,erick0z/ciao,mcastelino/ciao,matthewrsj/ciao,wcwxyz/ciao,erick0z/ciao,ciao-project/ciao,ciao-project/ciao,wcwxyz/ciao,leoswaldo/ciao,matthewrsj/ciao,mrkz/ciao,tpepper/ciao,obedmr/ciao,matthewrsj/ciao,chavafg/ciao