arm64_make script changes

TODO: Call this script from the bots with command sh -x arm64_make

Motivation: This will give the logs more complete information about
what the scripts are doing.

NOTRY=true
R=mtklein@google.com

Author: halcanary@google.com

Review URL: https://codereview.chromium.org/222803002

git-svn-id: http://skia.googlecode.com/svn/trunk@14032 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed