hostap: don't skip any headers in hostap_80211_header_parse()

Don't try to skip any headers in hostap_80211_header_parse().  We never
use that function for interfaces affected by local->monitor_type.  Both
the master and the AP interface receive 802.11 frames without any
additional headers.

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>