arm: dts: k3-binman: Add support for FIT templates

Add templates for FIT images used extensively across K3 boards with most
of the code common. This includes the FIT portions of:
	- tispl.bin
	- u-boot.img
	- sysfw.itb (in case of legacy boot flow)

Signed-off-by: Neha Malcom Francis <n-francis@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>