Import various DT files for am4372, an43xx pinctrl and
am437x-gp-evm from Linux Kernel v4.2
Add config file for this board, enable DM, DM_GPIO, DM_SERIAL
and DM_MMC.
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
