mmc: sdhci-esdhc-imx: pdev->id_entry should be immutable

As a good practice, device driver should not modify pdev->id_entry but
keep it immutable.  Let's assign of_device_id.data with imx_esdhc_type
constants directly, so that we do not have to manipulate pdev->id_entry
in .probe().

As the result, sdhci-esdhc-imx53 and sdhci-usdhc-imx6q can be removed
from platform_device_id table now, since they will only probe from
device tree.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Chris Ball <cjb@laptop.org>