mmc: sdhci-esdhc-imx: move all non dt probe code into one function

This is an incremental fix of commit
e62bd351b("mmc: sdhci-esdhc-imx: Do not break platform data boards").

After commit 8d86e4fc

 ("mmc: sdhci-esdhc-imx: Call mmc_of_parse()"),
we do not need to run the check of boarddata->wp_type/cd_type/max_bus_width
again for dt platform since those are already handled by mmc_of_parse().

Current code only exclude the checking of wp_type for dt platform which
does not make sense.

This patch moves all non dt probe code into one function.
Besides, since we only support SD3.0/eMMC HS200 for dt platform, the
support_vsel checking and ultra high speed pinctrl state are also merged
into sdhci_esdhc_imx_probe_dt.

Then we have two separately probe function for dt and non dt type.
This can make the driver probe more clearly.

Signed-off-by: Dong Aisheng <aisheng.dong@freescale.com>
Reviewed-by: Johan Derycke <johan.derycke@barco.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>