iwlwifi: mvm: rfi: use kmemdup() to replace kzalloc + memcpy

Fix memdup.cocci warning:
./drivers/net/wireless/intel/iwlwifi/mvm/rfi.c:110:8-15: WARNING
opportunity for kmemdup

Signed-off-by: Bixuan Cui <cuibixuan@linux.alibaba.com>
Link: https://lore.kernel.org/r/1635317920-84725-1-git-send-email-cuibixuan@linux.alibaba.com
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/rfi.c

@@ -125,12 +125,10 @@ struct iwl_rfi_freq_table_resp_cmd *iwl_rfi_get_freq_table(struct iwl_mvm *mvm)
 	if (WARN_ON_ONCE(iwl_rx_packet_payload_len(cmd.resp_pkt) != resp_size))
 		return ERR_PTR(-EIO);
 
-	resp = kzalloc(resp_size, GFP_KERNEL);
+	resp = kmemdup(cmd.resp_pkt->data, resp_size, GFP_KERNEL);
 	if (!resp)
 		return ERR_PTR(-ENOMEM);
 
-	memcpy(resp, cmd.resp_pkt->data, resp_size);
-
 	iwl_free_resp(&cmd);
 	return resp;
 }