Add build target to generated dependency graph

$ make dump-module-dependency | tee dep.dot
<remove preceeding debug comments>
$ dot -Tsvg -odep.svg dep.dot

Change-Id: I84cd6a6ff43bf323663de3573ed46c20cdb1e9b5
Signed-off-by: You-Sheng Yang (楊有勝) <vicamo@gmail.com>