drop spammy set -x debug logic

We seem to have a handle on things now, or at the very least, this
spam isn't helping with debugging.  It is making it very hard to
read real build failures on bots & dev systems though.

BUG=chromium:1011891
TEST=CQ passes

Change-Id: Ib221da68c6703f2569b72fed8743740dff8fe253
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/1918107
Reviewed-by: George Engelbrecht <engeg@google.com>
Tested-by: George Engelbrecht <engeg@google.com>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
2 files changed