avoid sdata null pointer dereference in ieee80211_ibss_add_sta.
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some APs have strict checking between associate and reassociate. In
a case when an AP is restarted during a connection, it denies the
mac80211 reassoc request since this is a new association for the AP.
To fix this problem, we need to check the status code against
WLAN_STATUS_REASSOC_NO_ASSOC and clear ifsta->prev_bssid_set in
handling the association failure response.
Signed-off-by: NZhu Yi <yi.zhu@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

|   CC      net/mac80211/ieee80211_sta.o
| In file included from linux/net/mac80211/ieee80211_sta.c:31:
| include2/asm/delay.h: In function '__const_udelay':
| include2/asm/delay.h:33: error: 'loops_per_jiffy' undeclared (first use in this function)
| include2/asm/delay.h:33: error: (Each undeclared identifier is reported only once
| include2/asm/delay.h:33: error: for each function it appears in.)
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add mac80211, the IEEE 802.11 software MAC layer.
Signed-off-by: NJiri Benc <jbenc@suse.cz>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>