spi: fsl: Kill mpc8xxx_spi_cleanup and convert fsl_espi_setup to use devm_kzalloc

In current code, master->cleanup and master->setup are not set in the same
function. This makes it hard to read and not good for code maintain.
One example is in fsl-spi.c, master->cleanup is overrided in mpc8xxx_spi_probe()
which leads to a memory leak.

This patch removes mpc8xxx_spi_cleanup() and converts fsl_espi_setup to use
devm_kzalloc so we don't need to take care of freeing memory.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
index e767f58..3cf7d65 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/drivers/spi/spi-fsl-espi.c
@@ -458,7 +458,7 @@
 		return -EINVAL;
 
 	if (!cs) {
-		cs = kzalloc(sizeof *cs, GFP_KERNEL);
+		cs = devm_kzalloc(&spi->dev, sizeof(*cs), GFP_KERNEL);
 		if (!cs)
 			return -ENOMEM;
 		spi->controller_state = cs;