Solaris make testsuite fixes. * tests/check10.test: When a rule fails, Solaris make will output the complete command that failed; in this case the test suite driver. Adjust the test to not bogusly match lines from the driver, rather than its output. * tests/distcleancheck.test: Avoid triggering VPATH rewriting, not desirable in this test. * tests/specflg10.test: Use BUILT_SOURCES to specify an intermediate target, so Solaris make knows what to do. Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>