soc: swr-mstr: Fix headset detect issue during clk stop wakeup

When ext clk stop wakeup and slave_pending_irq come together
then interrupt at swrslave is cleared due to calling
enable_slave_irq. Do not clear interrupts for enable_slave_irq
when its called from clk stop wakeup.

Change-Id: Ia710030ab80306d6750bea7264f0d4c07053d701
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>