ARM: dts: add support for AM437x IDK

ARM: dts: add support for AM437x IDK

The AM437x Industrial Development Kit (IDK) is
an application development platform targeted at
industrial communication and control applications.

It comes with a 3-phase motor driver, PROFINET,
PROFIBUS and a few other industrial communication
interfaces.

The board has 1GiB of DDR3 RAM, QSPI NOR flash,
a 100% discrete power design (no PMIC) and an
on-board 2MP camera (not supported with Linux
as of this writing).

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>