CHROMIUMOS: nl80211: Fix size of scan flags

CHROMIUMOS: nl80211: Fix size of scan flags

Commit "nl80211: add api to abort a scan request on tx" specifies
a U32 for the scan flags parameter, but only sends a U8 when reporting
the scan event.  Fix this discrepancy.

Signed-off-by: Paul Stewart <pstew@chromium.org>
BUG=chromium-os:20999
TEST=Make sure "iw event" continues to work correctly (nobody
depends on the flags parameter to the scan event yet).

Change-Id: I8ecb81ac23ad908fcb6ccb0d606e1d2749120d17
Reviewed-on: http://gerrit.chromium.org/gerrit/8499
Reviewed-by: Sam Leffler <sleffler@chromium.org>
Tested-by: Paul Stewart <pstew@chromium.org>