manibuilder: Make Git remote overridable

Change-Id: Idfc1272f5a7370d3a183835ddf4052db374d6a26
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/70909
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: Nico Huber <nico.h@gmx.de>
diff --git a/util/manibuilder/Makefile b/util/manibuilder/Makefile
index c4f9333..31577c2 100644
--- a/util/manibuilder/Makefile
+++ b/util/manibuilder/Makefile
@@ -50,6 +50,7 @@
 $(filter centos%,$(MULTIARCH_TAGS)): MAKEARGS+=WARNERROR=no
 $(ALL_TAGS): export QUIET_SETUP=$(QUIET_TEST)
 $(ALL_TAGS): export TEST_REVISION?=master
+$(ALL_TAGS): export TEST_REMOTE?=origin
 $(ALL_TAGS): %: %-check-build
 	$(QUIET_TEST)docker rm -f mani_$(call ident,$*) >/dev/null 2>&1 || true
 	$(QUIET_TEST)\
@@ -57,7 +58,7 @@
 		--env IDENT=$(call ident,$*) \
 		--volume manicache:/home/mani/.ccache \
 		--name mani_$(call ident,$*) mani/$* \
-		"git fetch origin $(TEST_REVISION) && \
+		"git fetch $(TEST_REMOTE) $(TEST_REVISION) && \
 		 git checkout FETCH_HEAD && \
 		 $(MAKECMD) clean && $(MAKECMD) -j$${CPUS:-1} CC='$(CC)' \
 		 $(if $(STRIP),STRIP='$(STRIP)') \