mmc: sdhci-esdhc-imx: switch standard tuning to manual tuning

Current standard tuning has some limitations:

1. Standard tuning only try 40 times to find first pass window, but this
pass window maybe not the best pass window.

2. Sometimes there are two tuning pass windows and the gap between
those two windows may only have one cell. If tuning step > 1, the gap may
just be skipped and host assumes those two windows as a continuous
windows. This will cause a bad delay cell near the gap to be selected.

3. Standard tuning logic need to detect at least one success and failure
to pass the tuning. If all cells in the tuning window pass, the hardware
will not set the SDHCI_CTRL_TUNED_CLK bit, causing tuning failed.

4. Standard tuning logic only check the CRC, do not really compare the data
pattern. If data pins are connected incorrectly, standard will not detect
this kind of issue.

Switch to manual tuning to avoid those limitations

Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20250409075550.3413032-7-ziniu.wang_1@nxp.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

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