eMMC: explicitly indicate to the eMMC to handle sector type of addressing.

When in access mode validationi step, explicitly indicate to the eMMC
that the host is capable of handling sector type of addressing,
not depending on asking eMMC

To fix issue: fail to read eMMC(Micron Technology, P/N N2M400HDB321A3C - 16GB)

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>