tools: Allow 'make dist' from srcdir to work

This is because we already have a dist directory, and
in our wrapper makefile we have to mark 'DIST' as phony
target.

https://www.gnu.org/software/make/manual/html_node/Phony-Targets.html

Reviewed-by: Dominik Perpeet <dperpeet@redhat.com>

tools/Makefile.redirect

@@ -1,6 +1,9 @@
 # This redirects all make targets to builddir
+.PHONY: dist
 all:
 	$(MAKE) $(ARG) -C $(REDIRECT) all
+dist:
+	$(MAKE) $(ARG) -C $(REDIRECT) dist
 %:
 	$(MAKE) $(ARG) -C $(REDIRECT) $@
 ifeq ($(MAKEFLAGS), )