mmc: sdio: avoid using NULL sdio_irq_thread pointer
mmc: sdio: avoid using NULL sdio_irq_thread pointer

For Freescale QorIQ LS1021AQDS board, there is a SDIO interrupt
in the process of resume without inserting SD adapter because of
some unknown issue. But the driver doesn't assign sdio_irq_thread
pointer. This will block the resume of kernel. This patch is used
to avoid using NULL sdio_irq_thread pointer.

Signed-off-by: Yangbo Lu <8e8a9cf964d9a1c714752d84c97dd816751bdd12@freescale.com>
Signed-off-by: Ulf Hansson <fe47b31f388f85ce6ddf64bf3a0cf6b46077d0e6@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs