serial: sh-sci: Stop using deprecated dmaengine_terminate_all()

As of commit b36f09c3 ("dmaengine: Add transfer termination
synchronization support"), dmaengine_terminate_all() is deprecated.

Replace calls to dmaengine_terminate_all() in DMA release code by calls
to dmaengine_terminate_sync(), as the latter waits until all running
completion callbacks have finished.

Replace calls to dmaengine_terminate_all() in DMA failure paths by calls
to dmaengine_terminate_async(), as these are usually done in atomic
context.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>