mfd: wcd9xxx_irq: Fix the condition to lock/unlock sleep

When codec raises interrupt and the system is suspended, the driver
waits for parent to resume. Fix the condition in wait_for_event to
prevent checking against stale value of suspend state during wait.

CRs-fixed: 554056
Change-Id: If36f366861ec28b52d621a884853e8a9467fa337
Signed-off-by: Bhalchandra Gajare <gajare@codeaurora.org>