ARM: dts: stm32: Repair SDMMC2 operation

ARM: dts: stm32: Repair SDMMC2 operation

The eMMC uses different pinmux for the top four data lines, use such
a pinmux, otherwise it takes a very long time until the test for 8bit
operation times out. And this is the correct pinmux per schematic too.

Reviewed-by: Patrice Chotard <[email protected]>
Reviewed-by: Patrick Delaunay <[email protected]>
Signed-off-by: Marek Vasut <[email protected]>
Cc: Manivannan Sadhasivam <[email protected]>
Cc: Patrick Delaunay <[email protected]>
Cc: Patrice Chotard <[email protected]>