iwlwifi: dbg: don't stop dbg recording before entering D3 from 9000 devices

From 9000 device family the FW automatically stops the debug
recording and the driver should not stop it as well.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>