wl12xx: remove TIM ie from probe response

wl12xx uses the beacon as the probe response template.
However, the beacon includes a TIM ie, which shouldn't
exist in the probe response.

Delete it from the skb before configuring the probe
response template.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>