iw: fix pointer arithmetic in __print_he_capa

Found by fuzzing with clang fuzzer.

Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
Link: https://lore.kernel.org/r/20210213114853.17276-1-markus.theil@tu-ilmenau.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
1 file changed