am62a: dts: binman: Package tiboot3.bin, tispl.bin, u-boot.img

Support added for HS and GP boot binaries for AM62ax.

tiboot3.bin, tispl.bin and u-boot.img: For HS-SE devices
tiboot3.bin_fs, tispl.bin and u-boot.img: For HS-FS devices
tiboot3.bin_unsigned, tispl.bin_unsigned and u-boot.img_unsigned: For GP
devices

It is to be noted that the bootflow followed by AM62ax requires:

tiboot3.bin:
	* R5 SPL
	* R5 SPL dtbs
	* TIFS
	* board-cfg
	* pm-cfg
	* sec-cfg
	* rm-cfg

tispl.bin:
	* DM
	* ATF
	* OPTEE
	* A72 SPL
	* A72 SPL dtbs

u-boot.img:
	* A72 U-Boot
	* A72 U-Boot dtbs

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