iwlwifi: mvm: don't set the MCAST queue in STA's queue list

commit 837fb69f10588caafc883c4473a864660e1403ce upstream.

The MCAST queue should be enabled after DTIM only.
According to fw API, the MCAST must not be attached to any
station, but should appear in the mcast_qid of the AP's
mac context only.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>