build_image: drop sudo when using mkfs on non-root files

The use of sudo here is just to get a $PATH that includes these tools.
There's no need to run these as root since we're working on files the
user has created.

BUG=None
TEST=build_image still works

Change-Id: I2d10bcb795606bd118666097d78e94370391b2ec
Reviewed-on: https://gerrit.chromium.org/gerrit/49368
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Queue: David James <davidjames@chromium.org>
1 file changed