iwlwifi: fix max_ht_ampdu_exponent for older devices

The commit below didn't update the max_ht_ampdu_exponent
for the devices listed in iwl-[1-6]000.c which, in result,
became 0 instead of 8K. This reduced the size of the Rx
AMPDU from 64K to 8K which had an impact in the Rx
throughput. One user reported that because of this, his
downstream throughput droppped by a half.

CC: <stable@vger.kernel.org> [3.19]
Fixes: c064ddf318aa ("iwlwifi: change max HT and VHT A-MPDU exponent")
Reported-and-tested-by: Valentin Manea <linux-wireless@mrs.ro>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-1000.c b/drivers/net/wireless/iwlwifi/iwl-1000.c
index c3817fa..06f6cc0 100644
--- a/drivers/net/wireless/iwlwifi/iwl-1000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-1000.c
@@ -95,7 +95,8 @@
 	.nvm_calib_ver = EEPROM_1000_TX_POWER_VERSION,	\
 	.base_params = &iwl1000_base_params,			\
 	.eeprom_params = &iwl1000_eeprom_params,		\
-	.led_mode = IWL_LED_BLINK
+	.led_mode = IWL_LED_BLINK,				\
+	.max_ht_ampdu_exponent = IEEE80211_HT_MAX_AMPDU_64K
 
 const struct iwl_cfg iwl1000_bgn_cfg = {
 	.name = "Intel(R) Centrino(R) Wireless-N 1000 BGN",
@@ -121,7 +122,8 @@
 	.base_params = &iwl1000_base_params,			\
 	.eeprom_params = &iwl1000_eeprom_params,		\
 	.led_mode = IWL_LED_RF_STATE,				\
-	.rx_with_siso_diversity = true
+	.rx_with_siso_diversity = true,				\
+	.max_ht_ampdu_exponent = IEEE80211_HT_MAX_AMPDU_64K
 
 const struct iwl_cfg iwl100_bgn_cfg = {
 	.name = "Intel(R) Centrino(R) Wireless-N 100 BGN",