build: use shorthand lint target from test

Instead of invoking jslint/cpplint from the test target,
call on the generic lint instead since it checks if eslint
exists. Since our tarballs lacks eslint we now get a more graceful
exit from `make test` instead of a traceback from jslint.

PR-URL: #6406
Fixes: #6408
Reviewed-By: Ryan Graham <r.m.graham@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

Makefile

@@ -115,9 +115,9 @@ v8:
 	$(MAKE) -C deps/v8 $(V8_ARCH) $(V8_BUILD_OPTIONS)
 
 test: | cctest  # Depends on 'all'.
-	$(PYTHON) tools/test.py --mode=release doctool message parallel sequential -J
-	$(MAKE) jslint
-	$(MAKE) cpplint
+	$(PYTHON) tools/test.py --mode=release -J \
+		doctool message parallel sequential
+	$(MAKE) lint
 
 test-parallel: all
 	$(PYTHON) tools/test.py --mode=release parallel -J