mei: use helper function to find me client by id

We already have a helper to find me client by id, let's
use it in all relevant places.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc drivers/misc/mei/client.c
Simple merge

diff --cc drivers/misc/mei/hbm.c
Simple merge