dmaengine: imx-sdma: add missed braces

The "if" conditional statement is not a single statement,
so both branches require braces.

Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
Link: https://lore.kernel.org/r/20210928151833.589843-2-f.suligoi@asem.it


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