tests: avoid '$MAKE' redirections, use 'run_make' instead The use 'run_make' with the -E, -O and -M option, it is more idiomatic now. Also, this way, centralized fixes and improvements done in 'run_make' will automatically propagate through most of the testsuite. * syntax-checks.mk (sc_tests_no_run_make_redirect): Also check against '$MAKE' invocations that uses output redirections (and not only against 'run_make' invocation that do so). * Several tests: Adjust (and few minor cosmetic changes as well, while at it). Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>