staging: wfx: fix overflow in frame counters

staging: wfx: fix overflow in frame counters

It has been reported that trying to send small packets of data could
produce a "inconsistent notification" warning.

It seems that in some circumstances, the number of frame queued in the
driver could greatly increase and exceed UCHAR_MAX. So the field
"buffered" from struct sta_priv can overflow.

Just increase the size of "bueffered" to fix the problem.

Fixes: 7d2d2bfdeb82 ("staging: wfx: relocate "buffered" information to sta_priv")
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200427134031.323403-10-Jerome.Pouiller@silabs.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>