This commit includes:
- use `DEPENDS =` instead of `DEPENDS +=`.
- put single-line configurations into a single line
- move DEPENDS to right location in recipe files
- remove superfluous ROS_SPN declarations
The clean up was motivated by the commits for
object-recognition-msgs and hector-mapping in #519.
Issues were identified with `grep "DEPENDS +=" . -R` and by looking
at the output of oe-stylize.py with this bash script:
```
for RECIPE in $(find . -name *.bb)
do
echo "Processing: $RECIPE"
~/work/repositories/openembedded.org/meta-openembedded/contrib/oe-stylize.py $RECIPE > $RECIPE-oestylize
diff $RECIPE $RECIPE-oestylize
done
```
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>