Build error after radiotap update

[Matteo Croce]

Hi,

After e6ac26943 ("radiotap: Update radiotap parser")
I get this build error:

# make
/usr/bin/ld: build/hostapd/src/drivers/driver_nl80211_monitor.o:src/utils/radiotap.h:42: multiple definition of `__packed'; build/hostapd/src/drivers/driver_nl80211.o:src/utils/radiotap.h:42: first defined here
/usr/bin/ld: build/hostapd/src/utils/radiotap.o:hostapd/../src/utils/radiotap.h:42: multiple definition of `__packed'; build/hostapd/src/drivers/driver_nl80211.o:src/utils/radiotap.h:42: first defined here
collect2: error: ld returned 1 exit status
make: *** [Makefile:1281: hostapd] Error 1

I tried to replace __packed with __attribute__ ((__packed__)) and
although it compiles, I have the following warning:

../src/utils/radiotap.c: In function ‘ieee80211_radiotap_iterator_init’:
../src/utils/radiotap.c:114:27: warning: taking address of packed member of ‘struct ieee80211_radiotap_header’ may result in an unaligned pointer value [-Waddress-of-packed-member]
  114 |  iterator->_next_bitmap = &radiotap_header->it_present;
      |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

My compiler is: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Regards,
-- 
per aspera ad upstream