Omit the definiton of src_install() if it matches the default

The default is defined in src_install.mgwpart.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Omit the definiton of src_test() if it matches the default

The default is defined in src_test.mgwpart.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>