replace Debian software repository with eLxr ones for image build

We do not need to specify the eLxr software repository URL explicitly under "mirrors" in the YAML configuration files because the mmdebstrap already defaults to eLxr software repository [1].

We shall use "components" [2] in the YAML configuration file to specify the additional components from eLxr Aria.

[1] elxr/debian/mmdebstrap@f5cf599d

[2] https://gitlab.com/elxr/tools/pasha/-/blob/031d8526e38751dc75da277d36a505373047939f/pasha/modules/bootstrap.py#L88-92

Signed-off-by: William Lyu William.Lyu@windriver.com