filesystem-sanity: Remove factory from BAD_VAR_PACKAGES

We don't allow packages to install into /var because it's not guaranteed
to be stable across reboots.

BUG=b:172200612
TEST=emerge-${BOARD} factory factory-board

Change-Id: Ic2ba710ba637cf424725dda13c47a3b72b225930
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/2545339
Tested-by: Cheng Yueh <cyueh@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Cheng Yueh <cyueh@chromium.org>
diff --git a/hooks/filesystem-sanity.py b/hooks/filesystem-sanity.py
index a749528..71efaf9 100755
--- a/hooks/filesystem-sanity.py
+++ b/hooks/filesystem-sanity.py
@@ -105,9 +105,6 @@
     'chromeos-base/chromeos-initramfs',
     # https://crbug.com/1054646
     'chromeos-base/devserver',
-    # https://crbug.com/1007402
-    'chromeos-base/factory',
-    'chromeos-base/factory-board',
     'dev-python/django',
     'media-gfx/sane-backends',
     'media-sound/alsa-utils',