mmc: fsl_esdhc: support eMMC HS400 mode

mmc: fsl_esdhc: support eMMC HS400 mode

The process for eMMC HS400 mode for eSDHC is,

1. Perform the Tuning Process at the HS400 target operating frequency.
   Latched the clock division value.
2. if read transaction, then set the SDTIMNGCTL[FLW_CTL_BG].
3. Switch to High Speed mode and then set the card clock frequency to
   a value not greater than 52Mhz
4. Clear TBCTL[TB_EN],tuning block enable bit.
5. Change to 8 bit DDR Mode
6. Switch the card to HS400 mode.
7. Set TBCTL[TB_EN], tuning block enable bit.
8. Clear SYSCTL[SDCLKEN]
9. Wait for PRSSTAT[SDSTB] to be set
10. Change the clock division to latched value.Set TBCTL[HS 400 mode]
    and Set SDCLKCTL[CMD_CLK_CTRL]
11. Set SYSCTL[SDCLKEN]
12. Wait for PRSSTAT[SDSTB] to be set
13. Set DLLCFG0[DLL_ENABLE] and DLLCFG0[DLL_FREQ_SEL].
14. Wait for delay chain to lock.
15. Set TBCTL[HS400_WNDW_ADJUST]
16. Again clear SYSCTL[SDCLKEN]
17. Wait for PRSSTAT[SDSTB] to be set
18. Set ESDHCCTL[FAF]
19. Wait for ESDHCCTL[FAF] to be cleared
20. Set SYSCTL[SDCLKEN]
21. Wait for PRSSTAT[SDSTB] to be set.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>