Avoid skipping test if it's supported.

Previously the test will be skipped regardless whether setThreads is
supported, this patch moves the check below and check the returned
status code to determine whether the test should be skipped.

Bug: b/287282833
Test: atest VtsHalPowerTargetTest
Change-Id: I9ce6b4ead5e245478247903a75922ece74f38ee7
1 file changed