The previous code was using IWEVCUSTOM to report IEs from AssocReq and
AssocResp frames into user space. This can easily hit the 256 byte
limit (IW_CUSTOM_MAX) with APs that include number of vendor IEs in
AssocResp. This results in the event message not being sent and dmesg
showing "wlan0 (WE) : Wireless Event too big (366)" type of errors.

Convert mac80211 to use IWEVASSOCREQIE/IWEVASSOCRESPIE to avoid the
issue of being unable to send association IEs as wireless events. These
newer event types use binary encoding and larger maximum size
(IW_GENERIC_IE_MAX = 1024), so the likelyhood of not being able to send
the IEs is much smaller than with IWEVCUSTOM. As an extra benefit, the
code is also quite a bit simpler since there is no need to allocate an
extra buffer for hex encoding.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>