iwlwifi: pcie: centralize SCD status logging

Centralize the logging of SCD status. The motivation is
that for a000 devices we will have new SCD HW, but this
code was duplicate anyway, so it is a proper cleanup.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>