cligen: update git submodule

Signed-off-by: Daiki Ueno <ueno@gnu.org>

diff --git a/cligen b/cligen
index be900385825c05fe3c672d2aed02f060790d2d18..ed2ed7b19a5bcbc0f39505722058befc923eeeda 160000 (submodule)
--- a/cligen
+++ b/cligen
@@ -1 +1 @@
-Subproject commit be900385825c05fe3c672d2aed02f060790d2d18
+Subproject commit ed2ed7b19a5bcbc0f39505722058befc923eeeda