omap3_logic: Add Device Tree Support and more DM drivers

This patch also removes all the excessive code for NS16550 intiailization
as the device tree can do that now.  This also adds DM_I2C and DM_MMC
since the overlying drivers have the built-in support already.  The
corresponding include/config/omap3_logic.h also reduced in size
due to the new device tree support.

Signed-off-by: Adam Ford <aford173@gmail.com>

Changes in V2:
  Retain Auto-detect ability between SOM-LV and Torpedo
  Split this off from the device sub submissions