* Makefile.am (maintainer-check): Check for misuses of make, autoconf, automake, aclocal, and perl in the testsuite. Suggest using $MAKE, $AUTOCONF, $AUTOMAKE, $ACLOCAL, and $PERL instead. * tests/confsub.test: Use $AUTOCONF and $MAKE. * tests/extra5.test, tests/extra6.test, tests/lex5.test, tests/nobase.test, tests/nodist2.test, tests/pr204.test, tests/pr224.test, tests/pr287.test, tests/strip.test, tests/yacc8.test: Use $MAKE.