dmaengine: img-mdc: Remove unnecessary synchronize_irq() before devm_free_irq()

Calling synchronize_irq() right before devm_free_irq() is quite useless. On
one hand the IRQ can easily fire again before devm_free_irq() is entered,
on the other hand devm_free_irq() itself calls synchronize_irq() internally
(in a race condition free way), before any state associated with the IRQ is
freed.

Patch was generated using the following semantic patch:
// <smpl>
@@
expression irq, dev;
@@
-synchronize_irq(irq);
 devm_free_irq(dev, irq, ...);
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>