staging: wfx: fix CAB sent at the wrong time

wfx_suspend_resume_mc() is called when the device is about to sent a
DTIM. This is the right moment to enqueue Content After DTIM Beacon
(CAB).

However, wfx_suspend_resume_mc() is also called when the DTIM period
ends. Until now, this event did also trig CAB.

Note this issue did not have too much impact since when a CAB is sent
outside of DTIM window, an error is reported by the firmware and
mac80211 retries to send the data.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200427134031.323403-6-Jerome.Pouiller@silabs.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>