dma: imx-sdma: Print a message when firmare fails to be requested

Print a message when firmare fails to be requested in the case of platform data being used.

While at it, distinguish between the error messages of the device tree and platform data cases.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>