selftests: sync: convert to use TAP13 ksft framework

Convert test to use TAP13 ksft framework. Output after conversion:

TAP version 13
# [RUN]	Testing sync framework
ok 1 [RUN]	test_alloc_timeline
ok 2 [RUN]	test_alloc_fence
ok 3 [RUN]	test_alloc_fence_negative
ok 4 [RUN]	test_fence_one_timeline_wait
ok 5 [RUN]	test_fence_one_timeline_merge
ok 6 [RUN]	test_fence_merge_same_fence
ok 7 [RUN]	test_fence_multi_timeline_wait
ok 8 [RUN]	test_stress_two_threads_shared_timeline
ok 9 [RUN]	test_consumer_stress_multi_producer_single_consumer
ok 10 [RUN]	test_merge_stress_random_merge
Pass 10 Fail 0 Xfail 0 Xpass 0 Skip 0
1..10

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>