iwlwifi: read MAC address from correct place on Bz

On Bz devices, the MAC address CSRs changed from 0x380 to 0x30.
Change the boolean configuration "mac_addr_from_csr" to hold the
base address instead, and set it correctly for the different
devices using this feature.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20210802215208.928c7983f014.Ic5ba92d98946c1b4640280a05dcfd75119c0f0c0@changeid
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>