TI: OMAP5: add dtb name for DRA72-evm

DRA72-evm is a new platform using DRA72x Silicon. Add support for dtb
name in findfdt

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
TI: OMAP5: Add find_fdt support for BeagleBoard-X15

BeagleBoard X15 uses AM5728 processor - add support for the findfdt to
identify the right dtb

Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>