overlays: Fix misnamed overlays.

Update repo_name in:
  overlay-amd64-corei7
  overlay-amd64-drm

BUG=chromium:889662
TEST=cros_mark_as_stable --dryrun

Change-Id: I355311d557ee4137de5d7795b01596ed84f8340d
Reviewed-on: https://chromium-review.googlesource.com/1257099
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
diff --git a/overlay-amd64-corei7/profiles/repo_name b/overlay-amd64-corei7/profiles/repo_name
index f8c48ee..af2ae21 100644
--- a/overlay-amd64-corei7/profiles/repo_name
+++ b/overlay-amd64-corei7/profiles/repo_name
@@ -1 +1 @@
-amd64-generic
+amd64-corei7
diff --git a/overlay-amd64-drm/profiles/repo_name b/overlay-amd64-drm/profiles/repo_name
index 5789775..d3a80aa 100644
--- a/overlay-amd64-drm/profiles/repo_name
+++ b/overlay-amd64-drm/profiles/repo_name
@@ -1 +1 @@
-x86-drm
+amd64-drm