Update rebar in autopatch

This should fix some Windows issues.

core/deps.mk

@@ -163,7 +163,7 @@ define dep_autopatch_fetch_rebar
 	if [ ! -d $(ERLANG_MK_TMP)/rebar ]; then \
 		git clone -q -n -- https://github.com/rebar/rebar $(ERLANG_MK_TMP)/rebar; \
 		cd $(ERLANG_MK_TMP)/rebar; \
-		git checkout -q 791db716b5a3a7671e0b351f95ddf24b848ee173; \
+		git checkout -q 576e12171ab8d69b048b827b92aa65d067deea01; \
 		$(MAKE); \
 		cd -; \
 	fi