util/misc_util: Fix unchecked error

It's unlikely, but let's check for ftell() errors.

BUG=b:64477774
BRANCH=none
TEST=none

Change-Id: I3690da60f756ab056e852e9f485b3c439c82e67b
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Found-by: Coverity Scan #58158
Reviewed-on: https://chromium-review.googlesource.com/719196
Commit-Ready: Patrick Georgi <pgeorgi@chromium.org>
Tested-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-by: Martin Roth <martinroth@chromium.org>
1 file changed