Restore abandoned lines in bridges/Library_cpp_uno.mk

Fixes build error:
    bridges/Module_bridges.mk:29: *** no bridge selected for build: bailing out. Stop.

Change-Id: I1d173e75ade45878e53ed07758783bdb5a7370c8
Signed-off-by: Stephan Bergmann <sbergman@redhat.com>