Update object-mapper.md link

object-mapper.md is moving under architecture/ as part of
https://gerrit.openbmc-project.xyz/c/openbmc/docs/+/26250/

26250 should merge before this is merged.

Change-Id: Icf4ace8d827cd6fbfb61f41008b4662635755a3c
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/README.md b/README.md
index ca640e0..a12f0c4 100644
--- a/README.md
+++ b/README.md
@@ -225,4 +225,4 @@
 ```
  ./bootstrap.sh clean
 ```
-[1]: https://github.com/openbmc/docs/blob/master/object-mapper.md#associations
+[1]: https://github.com/openbmc/docs/blob/master/architecture/object-mapper.md#associations