add .gitreview to support git review plugin

Change-Id: If8ebdb687f41911f55679472a0c87f9734264e80
diff --git a/.gitreview b/.gitreview
new file mode 100644
index 0000000..b8af595
--- /dev/null
+++ b/.gitreview
@@ -0,0 +1,3 @@
+[gerrit]
+host=gerrit.osmocom.org
+project=osmo-iuh