ARM: dts: Add basic devices for AM3517-craneboard

Craneboard is a hardware development platform based on the Sitara
AM3517 ARM Cortex - A8 microprocessor device - see [1] for more
details. Add basic devices for craneboard as replacement for the board
file scheduled for removal as part of device tree conversion

[1] http://craneboard.org



Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Benoit Cousson <bcousson@baylibre.com>