tests: avoid spurious failure with older flex (2.5.4) That old version is unfortunately still relevant, being the one installed on NetBSD 5.1. * t/lex-multiple.sh: Use the '-o' option rather than the longer equivalent '--outfile'. The latter is not supported by older versions of flex (e.g., flex 2.5.4). Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>