iwl4965: workaround connection regression on passive channel

Jake reported that since commit 1672c0e3
"mac80211: start auth/assoc timeout on frame status", he is unable to
connect to his AP, which is configured to use passive channel.

After switch to passive channel 4965 firmware drops any TX packet until
it receives beacon. Before commit 1672c0e3 we waited on channel and
retransmit packet after 200ms, that makes we receive beacon on the
meantime and association process succeed. New mac80211 behaviour cause
that any ASSOC frame fail immediately on iwl4965 and we can not
associate.

This patch restore old mac80211 behaviour for iwl4965, by removing
IEEE80211_HW_REPORTS_TX_ACK_STATUS feature. This feature will be
added again to iwl4965 driver, when different, more complex
workaround for this firmware issue, will be added to the driver.

Cc: stable@vger.kernel.org # 3.9
Bisected-by: NJake Edge <jake@lwn.net>
Reported-and-tested-by: NJake Edge <jake@lwn.net>
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlegacy/4965-mac.c

@@ -5741,8 +5741,7 @@ il4965_mac_setup_register(struct il_priv *il, u32 max_probe_length)
 	hw->flags =
 	    IEEE80211_HW_SIGNAL_DBM | IEEE80211_HW_AMPDU_AGGREGATION |
 	    IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC | IEEE80211_HW_SPECTRUM_MGMT |
-	    IEEE80211_HW_REPORTS_TX_ACK_STATUS | IEEE80211_HW_SUPPORTS_PS |
-	    IEEE80211_HW_SUPPORTS_DYNAMIC_PS;
+	    IEEE80211_HW_SUPPORTS_PS | IEEE80211_HW_SUPPORTS_DYNAMIC_PS;
 	if (il->cfg->sku & IL_SKU_N)
 		hw->flags |=
 		    IEEE80211_HW_SUPPORTS_DYNAMIC_SMPS |