bug fix: restore support for broken flag

timestampDevTest flag can be used to disable timestamp deviation
tests. The flag is not working as intended. This is corrected.

Test: make vts -j99 BUILD_GOOGLE_VTS=true TARGET_PRODUCT=aosp_arm64 \
&& vts-tradefed run commandAndExit vts \
--skip-all-system-status-check --primary-abi-only \
--skip-preconditions --module VtsHalMediaOmxV1_0Test -l INFO

Bug: 64743270
Bug: 65166112

Merged-In: I611e96498a4677b6ccbff33c291d56eed7b48f6f
Change-Id: I611e96498a4677b6ccbff33c291d56eed7b48f6f
(cherry picked from commit dc6270ec)