Clean up and test make clean

.travis.sh

@@ -22,3 +22,5 @@ arm32)
 esac
 
 $LOADER make check
+
+make clean && git status --ignored --porcelain && test -z "$(git status --ignored --porcelain)"

Makefile

@@ -51,14 +51,9 @@ test/test-float: libopenlibm.$(SHLIB_EXT)
 	$(MAKE) -C test test-float
 
 clean:
-	@for dir in $(SUBDIRS) .; do \
-		rm -fr $$dir/*.o $$dir/*.a $$dir/*.$(SHLIB_EXT)*; \
-	done
-	@rm -f test/test-double test/test-float
-
-distclean:
-	-rm -f $(OBJS) *.a *.$(SHLIB_EXT) libopenlibm.*
-	-$(MAKE) -C test clean
+	rm -f amd64/*.o arm/*.o bsdsrc/*.o i387/*.o ld128/*.o ld80/*.o src/*.o
+	rm -f libopenlibm.a libopenlibm.$(SHLIB_EXT)*
+	$(MAKE) -C test clean
 
 openlibm.pc: openlibm.pc.in Make.inc Makefile
 	echo "prefix=${prefix}" > openlibm.pc