ASoC: fsl: Fix build problem

Commit 4324812 (ASoC: fsl-ssi: Use regmap) removed struct ccsr_ssi.
Unfortunately, the structure is still used. This causes
mpc85xx_smp_defconfig and mpc85xx_defconfig builds to fail with

sound/soc/fsl/fsl_dma.c:926:50:
  error: invalid use of undefined type 'struct ccsr_ssi'
  dma->ssi_stx_phys = res.start + offsetof(struct ccsr_ssi, stx0);
ound/soc/fsl/fsl_dma.c:927:50:
  error: invalid use of undefined type 'struct ccsr_ssi'
  dma->ssi_srx_phys = res.start + offsetof(struct ccsr_ssi, srx0);

Fix by using constants, similar to original commit.

Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/fsl/fsl_dma.c

@@ -923,8 +923,8 @@ static int fsl_soc_dma_probe(struct platform_device *pdev)
 	dma->dai.pcm_free = fsl_dma_free_dma_buffers;
 
 	/* Store the SSI-specific information that we need */
-	dma->ssi_stx_phys = res.start + offsetof(struct ccsr_ssi, stx0);
-	dma->ssi_srx_phys = res.start + offsetof(struct ccsr_ssi, srx0);
+	dma->ssi_stx_phys = res.start + CCSR_SSI_STX0;
+	dma->ssi_srx_phys = res.start + CCSR_SSI_SRX0;
 
 	iprop = of_get_property(ssi_np, "fsl,fifo-depth", NULL);
 	if (iprop)