Fix make clobber in 2001/herrmann1

2001/herrmann1/Makefile

@@ -201,7 +201,7 @@ clean:
 
 clobber: clean
 	${RM} -f ${TARGET} ${ALT_TARGET}
-	${RM} -rf *.dSYM
+	${RM} -rf *.dSYM error herrmann1-1.c herrmann1-3.c
 	@-if [ -e sandwich ]; then \
 	    ${RM} -f sandwich; \
 	    echo 'ate sandwich'; \