cfg80211: fix wext-compat for getting retry value

While getting the retry limit, wext-compat returns the value
without updating the flag for retry->flags is 0. Also in this
case, it updates long retry flag when short and long retry
value are unequal.

So, iwconfig never showing "Retry short limit" and showing
"Retry long limit" when both values are unequal.

Updated the flags and corrected the condition properly.

Signed-off-by: Ujjal Roy <royujjal@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>