Build - Fix the extra dt.img compilation issue.

Add support for optional device tree image (dt.img)
for device that doesnt have TARGET_BOOTIMAGE_USE_EXT2

Change-Id: I324f5d2e5d3a5235ea5a1be0542c52f7bc1b42b3
Signed-off-by: STELIX <ssspinni@gmail.com>
Build - Fixing Compilation issue

Change-Id: I1204fa22f160b880a692b0c18d1d04d1c31c8121
Signed-off-by: STELIX <ssspinni@gmail.com>