travis: Add check for configs without MAINTAINERS entries

The genboardscfg.py script will emit a WARNING message if we have new
defconfig files that are not listed in a MAINTAINERS file.  Make new
cases of this a failure we catch in Travis-CI.

Signed-off-by: Tom Rini <trini@konsulko.com>

.travis.yml

@@ -332,6 +332,10 @@ matrix:
     - name: "sloccount"
       script:
         - sloccount .
+    # ensure all configs have MAINTAINERS entries
+    - name: "Check for configs without MAINTAINERS entry"
+      script:
+        - if [ `./tools/genboardscfg.py -f 2>&1 | wc -l` -ne 0 ]; then exit 1; fi
 
     # test/py
     - name: "test/py sandbox"