add a `git-submodule` make target.

diff --git a/Makefile b/Makefile
index 59c2fa7b4f77f0dd60190ce69da3891284fbb47c..558cf473c4963a64e31428bb35ffae31e1bf4731 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -551,6 +551,10 @@ test: test-all
 .PHONY: test-clean
 test-clean: test-all-clean
 
+git-submodule:
+       git submodule sync --recursive
+       git submodule update --init --recursive
+
 ifdef SKIP_VERSION
 SKIP_GIT := yes
 endif