iwlwifi: exclude GEO SAR support for 3168

We currently support two NICs in FW version 29, namely 7265D and 3168.
Out of these, only 7265D supports GEO SAR, so adjust the function that
checks for it accordingly.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Fixes: f5a47fae

 ("iwlwifi: mvm: fix version check for GEO_TX_POWER_LIMIT support")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>