tests: avoid spurious failure when running as root Fixes automake bug#12041. * t/primary-prefix-couples-force-valid.sh: If run as root, don't expect a "test -x" on a non-executable files to fail: for root, all files are executable (as well as readable and writable), and at least on Solaris 10 that causes "test -x" to succeed also on non-executable files. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>