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 <peng.fan@nxp.com>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Jean-Jacques Hiblot <jjhiblot@ti.com>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Faiz Abbas <faiz_abbas@ti.com>
Cc: Marek Vasut <marex@denx.de>
Signed-off-by: Peng Fan <peng.fan@nxp.com>