runtime_probe: Add extra group entry

This CL adds a new group name cros_ec-access to allow secure ec info
retrieval for runtime_probe under minijail

BUG=chromium:908006, b:119155505
TEST=emerge-nami runtime_probe
Change-Id: I496377b14376e5fc26c0c6ac8342e861c2f01e0d
Reviewed-on: https://chromium-review.googlesource.com/1369482
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Hong-Min Chu <hmchu@chromium.org>
Reviewed-by: Mattias Nissler <mnissler@chromium.org>
diff --git a/profiles/base/accounts/group/cros_ec-access b/profiles/base/accounts/group/cros_ec-access
new file mode 100644
index 0000000..e5f127b
--- /dev/null
+++ b/profiles/base/accounts/group/cros_ec-access
@@ -0,0 +1,6 @@
+group:cros_ec-access
+gid:416
+# This group is to grant rw access to /dev/cros_ec
+# runtime_probe because the runtime_probe binary needs
+# access for probing information w/o being root
+users:runtime_probe