Fixing XOS Repo doc link error

Change-Id: I1d12797fe8c2172dbbbab5616d96a7c571c22fb0
diff --git a/docs/dev/xproto.md b/docs/dev/xproto.md
index af896f0..0ebd782 100644
--- a/docs/dev/xproto.md
+++ b/docs/dev/xproto.md
@@ -276,7 +276,7 @@
 
 For more information about declarative and feedback state, and the
 role they play in synchornizing the data model with the backend
-components, read about the [Synchronizer Architecture](dev/sync_arch.md). 
+components, read about the [Synchronizer Architecture](sync_arch.md). 
 
 ## Policies