XServiceInfo does not need to be declared as a supported sub-interface
for services, it is always implicitly there.
Also, for those services that now only contain one interface, convert
them to new-style service IDL declarations.

Change-Id: I325c27f287a02de6bdfc8bb6e5bf6c2a4ae0a753

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

I used this "one-liner" to detect comment lines containing
only spaces and '=' or '-'

$ find . -name "*.*" -exec sed -i '/^\s*\/\/\s*[-=]*\s*$/d' {} \;

Change-Id: Iac589765c8c2e7c3ad9c487d57e48b4fd4439f07