OWNERS: switch 'matches' to 'matchers'

The original OWNERS template had a mistake which used 'matches' instead
of the field supported by the Gerrit plugin 'matchers'.  Update the
OWNERS file to have the correct field.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I1275dc661e960493260d55944538e86b61ea1469
diff --git a/OWNERS b/OWNERS
index b488f79..340e0e9 100644
--- a/OWNERS
+++ b/OWNERS
@@ -20,7 +20,7 @@
 #   * reviewers: A list of individuals who have requested review notification
 #     on the repository.
 #
-#   * matches: A list of specific file/path matches for granular 'owners' and
+#   * matchers: A list of specific file/path matchers for granular 'owners' and
 #     'reviewers'.  See 'owners' plugin documentation.
 #
 #   * openbmc: A list of openbmc-specific meta-data about owners and reviewers.