Cleanup the code related to emit_interface_added

sdbusplus now supports action::emit_interface_added() when an object is
constructed, so the code that manually invokes emit_interface_added()
could be cleaned up and use the above action instead.

Tested: Verify the software objects are created as before, and BMC code
        update works fine.

Signed-off-by: Lei YU <mine260309@gmail.com>
Change-Id: I0b2ce4773c51f89f5b39b2d601173694c969d15b
2 files changed