[logging_CrashSender]: Don't hardcode autotest directory.

Not all platforms run autotest client code in /usr/local/autotest,
this updates crash_test.py so that it looks up the directory it
is running in on the DUT rather than hardcode in the path.

BUG=None.
TEST=test_that runs the test successfully on Moblab.

Change-Id: I1d512ffaec4e17079afb3e918ff7c364cb87a2fd
Reviewed-on: https://chromium-review.googlesource.com/213321
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Simran Basi <sbasi@chromium.org>
Commit-Queue: Simran Basi <sbasi@chromium.org>
1 file changed