maintcheck: avoid a couple of spurious failures * t/objcxx-deps.sh, t/objcxx-minidemo.sh: In C++ files, use "std::cout <<", not "cout <<", to avoid triggering a spurious failure by the syntax check 'sc_tests_here_document_format'. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>