staging: wfx: pspoll_mask make no sense

pspoll_mask is here to send data buffered in driver. But since station
is marked buffered, TIM for this station is 1 and mac80211 will call
sta_notify when a ps-poll is received. So pspoll_mask is useless and
sta_alseep_mask is sufficient.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20200115135338.14374-54-Jerome.Pouiller@silabs.com


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