Summary:
Having all of TMPD, TMPDIR and TEST_TMPDIR as configuration
parameters is confusing. This change simplifies a number of things by
standardizing on TEST_TMPDIR, while still recognizing the old names
also. In detail:
* crash_test.mk also needs to use TEST_TMPDIR for crash test, so put in
shared common.mk (an upgrade of python.mk)
* Always exporting TEST_TMPDIR eliminates the need to propagate TMPD or
export TEST_TMPDIR in selective places.
* Use --tmpdir option to gnu_parallel so that it doesn't need TMPDIR
environment variable
* Remove obsolete parloop and parallel_check Makefile targets
* Remove undefined, unused function ResetTmpDirForDirectIO()
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9961
Test Plan: manual + CI
Reviewed By: riversand963
Differential Revision: D36212178
Pulled By: pdillinger
fbshipit-source-id: b76c1876c4f4d38b37789c2779eaa7c3026824dd
