mtpd: Remove use of deprecated scoped_ptr_malloc.

BUG=none
TEST=emerge mtpd

Change-Id: I43e1da7c82bc2c7f96bf07dc67aa30db6b8c9a17
Reviewed-on: https://chromium-review.googlesource.com/190423
Tested-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
1 file changed