mac80211: mlme: find auth challenge directly

stable inclusion
from stable-v5.10.149
commit 66dacdbc2e830e1187bf0f1171ca257d816ab7e3
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0WY

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=66dacdbc2e830e1187bf0f1171ca257d816ab7e3

--------------------------------

There's no need to parse all elements etc. just to find the
authentication challenge - use cfg80211_find_elem() instead.
This also allows us to remove WLAN_EID_CHALLENGE handling
from the element parsing entirely.

Link: https://lore.kernel.org/r/20210920154009.45f9b3a15722.Ice3159ffad03a007d6154cbf1fb3a8c48489e86f@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>
Reviewed-by: Zheng Zengkai <zhengzengkai@huawei.com>