scripts: Makefile: Add multi overlay dtbo-base apply verify

Current board device tree overlay verify only support
single soc device tree dtb. Add support overlay apply verify
for multi soc device tree dtb in dtbo-base.

Change-Id: Idca1c57969303f701be37550da23c117cbd90470
Signed-off-by: Maria Yu <aiquny@codeaurora.org>