civetweb: update submodule to silence a compile warning

Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/civetweb b/src/civetweb
index 8d271315a541218caada366f84a2690fdbd474a2..061cd700231eb8e6e3e6e075e2245debb332b00c 160000 (submodule)
--- a/src/civetweb
+++ b/src/civetweb
@@ -1 +1 @@
-Subproject commit 8d271315a541218caada366f84a2690fdbd474a2
+Subproject commit 061cd700231eb8e6e3e6e075e2245debb332b00c