OWNERS.general: add myself

Interested in helping out with the review load.  I put myself in
g/cros-portage-reviewers already (not sure if that's needed for gwsq?)

BUG=none
TEST=presubmit

Change-Id: I7d8720e84acc9d685e7d477c915c578f120764c4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2490239
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
diff --git a/OWNERS.general b/OWNERS.general
index 6b6fef5..0a971fb 100644
--- a/OWNERS.general
+++ b/OWNERS.general
@@ -7,6 +7,7 @@
 allenwebb@google.com
 bmgordon@chromium.org
 chirantan@chromium.org
+jrosenth@chromium.org
 manojgupta@chromium.org
 
 include chromiumos/chromite:/OWNERS.build