mmc: add HS400 support

mmc: add HS400 support

Add HS400 support.
Selecting HS400 needs first select HS200 according to spec, so use
a dedicated function for HS400.
Add HS400 related macros.
Remove the restriction of only using the low 6 bits of
EXT_CSD_CARD_TYPE, using all the 8 bits.

Signed-off-by: Peng Fan <[email protected]>
Cc: Jaehoon Chung <[email protected]>
Cc: Jean-Jacques Hiblot <[email protected]>
Cc: Stefano Babic <[email protected]>
Cc: Kishon Vijay Abraham I <[email protected]>
Cc: Faiz Abbas <[email protected]>
Cc: Marek Vasut <[email protected]>
Signed-off-by: Peng Fan <[email protected]>