dmaengine: dw: platform: Move handle check to dw_dma_acpi_controller_register()

Move ACPI handle check to the dw_dma_acpi_controller_register().

While here, convert it to has_acpi_companion() which is recommended way.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20190820131546.75744-9-andriy.shevchenko@linux.intel.com


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