mei: hbm: drop hbm responses on shutdown

Ignore and drop HBM responses from init phase in shutdown phase.
Fixes stall if driver starting to stop in the middle of link init.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210129120752.850325-4-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>