runv: update submodule repo

Use a standalone cli repo so that it can be built inside the
kata runtime directory.

fixes: #17

Signed-off-by: Peng Tao <bergwolf@gmail.com>

.gitmodules

@@ -1,6 +1,6 @@
-[submodule "runv"]
-	path = runv
-	url = https://github.com/hyperhq/runv.git
 [submodule "cc-runtime"]
 	path = cc-runtime
 	url = https://github.com/clearcontainers/runtime
+[submodule "runvcli"]
+	path = runv
+	url = https://github.com/hyperhq/runvcli.git