dmaengine: imx-sdma: remove assignment never used

David reported:
[drivers/dma/imx-sdma.c:769]: (style) Variable 'emi_2_emi' is assigned a value that is never used

Since emi_2_emi is never used afterwards, remove thsi as well

Reported-by: David Binderman <dcb314@hotmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>