Sporadic llvm-test-suite failures on HIP back-end

Observed two flaky failures with HIP only:
1) UNRESOLVED: SYCL :: Assert/assert_in_simultaneously_multiple_tus.cpp
observed on two different patches:
https://github.com/intel/llvm/runs/7919414936?check_suite_focus=true
https://github.com/intel/llvm/runs/7972688959?check_suite_focus=true
[logs_48881.zip](https://github.com/intel/llvm/files/9408556/logs_48881.zip)

2) FAIL: SYCL:: Basic/buffer/buffer_dev_to_dev.cpp -
https://github.com/intel/llvm/runs/7951351745?check_suite_focus=true
https://github.com/intel/llvm/actions/runs/2911608931/attempts/2
[logs_49028.zip](https://github.com/intel/llvm/files/9408262/logs_49028.zip)