dmaengine: mediatek: hsdma_probe: fixed a memory leak when devm_request_irq fails

When devm_request_irq fails, currently, the function
dma_async_device_unregister gets called. This doesn't free
the resources allocated by of_dma_controller_register.
Therefore, we have called of_dma_controller_free for this purpose.

Signed-off-by: Satendra Singh Thakur <sst2005@gmail.com>
Link: https://lore.kernel.org/r/20191109113523.6067-1-sst2005@gmail.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>