fix distclean issues

deps/Makefile.am

@@ -42,18 +42,18 @@ dist-hook: dist-clean-protobuf dist-clean-protobuf-c dist-clean-mio
 
 dist-clean-protobuf:
 	if test -f $(distdir)/protobuf/Makefile; then          \
-		chmod +w `find $(distdir)/protobuf -type f`;   \
+		find $(distdir)/protobuf -type f |xargs chmod +x ;   \
                 echo "distclean:" > $(distdir)/protobuf/third-party/googletest/Makefile; \
 		make -C $(distdir)/protobuf distclean;         \
 	fi
 dist-clean-protobuf-c:
 	if test -f $(distdir)/protobuf-c/Makefile; then        \
-		chmod +w `find $(distdir)/protobuf-c -type f`; \
+		find $(distdir)/protobuf-c -type |xargs chmod +x ; \
 		make -C $(distdir)/protobuf-c distclean;       \
 	fi
 dist-clean-mio:
 	if test -f $(distdir)/mio/Makefile; then          \
-		chmod +w `find $(distdir)/mio -type f`;   \
+		find $(distdir)/mio -type f |xargs chmod +x ;   \
 		make -C $(distdir)/mio distclean;         \
 	fi