Update comment in device_management_backend.proto

It should not matter where the fields that fill `TpmStatusinfo`.

BUG=b:172748724
TEST=build ok.

Change-Id: Ic4dd4374ee25d9fc287ec02088b12cfe10f49035
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2586503
Commit-Queue: Leo Lai <cylai@google.com>
Reviewed-by: Maksim Ivanov <emaxx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836191}

components/policy/proto/device_management_backend.proto

@@ -2851,8 +2851,7 @@ message TpmVersionInfo {
   optional string vendor_specific = 6;
 }
 
-// Contains status of the TPM unit.  These fields come from GetTpmStatusReply
-// proto message from Chrome OS side (dbus/cryptohome/rpc.proto).
+// Contains status of the TPM unit.
 message TpmStatusInfo {
   optional bool enabled = 1;
   optional bool owned = 2;