Change name and document the bind_mount config paths

The content in these can be a file or a directory - so _dirs is
confusing. Change it to _paths and document it.

Change-Id: Ida38766cd3d440d75a6dc55035a54e0804e03760
diff --git a/doc/source/admin/components.rst b/doc/source/admin/components.rst
index 08671c9..e30966b 100644
--- a/doc/source/admin/components.rst
+++ b/doc/source/admin/components.rst
@@ -361,6 +361,26 @@
 
       disk_limit_per_job=100
 
+**trusted_ro_paths**
+
+  List of paths, separated by ':' to read-only bind mount into trusted
+  bubblewrap contexts.
+
+**trusted_rw_paths**
+
+  List of paths, separated by ':' to read-write bind mount into trusted
+  bubblewrap contexts.
+
+**untrusted_ro_paths**
+
+  List of paths, separated by ':' to read-only bind mount into untrusted
+  bubblewrap contexts.
+
+**untrusted_rw_paths**
+
+  List of paths, separated by ':' to read-write bind mount into untrusted
+  bubblewrap contexts.
+
 merger
 """"""