[OpenMP] Fix disabled 'libomptarget' tests

# Disabled tests

This issue tracks tests currently marked **XFAIL** or **UNSUPPORTED** in an effort to get the test suite in a workable state. As it stands, the test suite is flaky and often leads to zombie processes, system hangs, and other issues. These should be checked off as completed once the underlying issue has been resolved, but right now having functional testing is more important.

- [ ] [mapping/map_back_race.cpp](https://github.com/llvm/llvm-project/blob/main/offload/test/mapping/map_back_race.cpp)
- [ ] [mapping/map_both_pointer_pointee.c](https://github.com/llvm/llvm-project/blob/main/offload/test/mapping/map_both_pointer_pointee.c)
- [ ] [mapping/map_ptr_and_star_local.c](https://github.com/llvm/llvm-project/blob/main/offload/test/mapping/map_ptr_and_star_local.c)
- [ ] [mapping/map_structptr_and_member_global.c](https://github.com/llvm/llvm-project/blob/main/offload/test/mapping/map_structptr_and_member_global.c)
- [ ] [mapping/map_structptr_and_member_local.c](https://github.com/llvm/llvm-project/blob/main/offload/test/mapping/map_structptr_and_member_local.c)
- [ ] [offloading/CUDA/basic_launch_multi_arg.cu](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/CUDA/basic_launch_multi_arg.cu)
- [ ] [offloading/barrier_fence.c](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/barrier_fence.c)
- [ ] [offloading/bug51781.c](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/bug51781.c)
- [x] [offloading/fortran/declare-target-automap.f90](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/fortran/declare-target-automap.f90)
- [ ] [offloading/interop.c](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/interop.c)
- [ ] [offloading/single_threaded_for_barrier_hang_1.c](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/single_threaded_for_barrier_hang_1.c)
- [ ] [offloading/single_threaded_for_barrier_hang_2.c](https://github.com/llvm/llvm-project/blob/main/offload/test/offloading/single_threaded_for_barrier_hang_2.c)
- [ ] [sanitizer/ptr_outside_alloc_1.c](https://github.com/llvm/llvm-project/blob/main/offload/test/sanitizer/ptr_outside_alloc_1.c)
- [ ] [sanitizer/ptr_outside_alloc_2.c](https://github.com/llvm/llvm-project/blob/main/offload/test/sanitizer/ptr_outside_alloc_2.c)
- [ ] [sanitizer/use_after_free_1.c](https://github.com/llvm/llvm-project/blob/main/offload/test/sanitizer/use_after_free_1.c)
- [ ] [sanitizer/use_after_free_2.c](https://github.com/llvm/llvm-project/blob/main/offload/test/sanitizer/use_after_free_2.c)

Start with one unchecked test under offload/test, such as mapping/map_back_race.cpp or offloading/barrier_fence.c, and run it through the OpenMP offload test suite to reproduce its XFAIL or UNSUPPORTED status. Read the selected test and its failure output to identify the underlying issue. Done means the test runs reliably without hangs or zombie processes and its checklist item can be marked complete.

Written by the indexing model from the issue text.