[PATCH] hostap: Fix null pointer dereference in prism2_pccard_card_present()

With my Buffalo WLI-CF-S11G PC Card kernel oopses every time in
prism2_interrupt() when I try load the hostap module. local->hw_priv is null
during the first call to prism2_interrupt(). It feels like
interrupts are enabled too early, or something.

This patch fixes the symptom, but not the cause.

Signed-off-by: Kalle Valo <Kalle.Valo@iki.fi>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>