Restore gvc revision

Commit 9d54e46ce74698 accidentally reverted to a previous revision.

diff --git a/src/gvc b/src/gvc
index 03894efbcd010faf53bbc6e27256d27485f721b8..ed0ec4240125ac9f0a6d7502aa29644d37b2eac2 160000 (submodule)
--- a/src/gvc
+++ b/src/gvc
@@ -1 +1 @@
-Subproject commit 03894efbcd010faf53bbc6e27256d27485f721b8
+Subproject commit ed0ec4240125ac9f0a6d7502aa29644d37b2eac2