mac80211: Remove unused assignment statements

mac80211: Remove unused assignment statements

The assignment of these three local variables in the file will not
be used in the corresponding functions, so they should be deleted.

The clang_analyzer complains as follows:

net/mac80211/wpa.c:689:2 warning:
net/mac80211/wpa.c:883:2 warning:
net/mac80211/wpa.c:452:2 warning:

Value stored to 'hdr' is never read

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Link: https://lore.kernel.org/r/20211104061411.1744-1-luo.penghao@zte.com.cn
Signed-off-by: Johannes Berg <johannes.berg@intel.com>