[flang][OpenMP] trip count error compiling Fujitsu tests 0839_0000 0862_0001 0877_0024 0967_0000 0967_0004

Tests:
- https://github.com/fujitsu/compiler-test-suite/blob/main/Fortran/0839/0839_0000.f90
- https://github.com/fujitsu/compiler-test-suite/blob/main/Fortran/0862/0862_0001.f90
- https://github.com/fujitsu/compiler-test-suite/blob/main/Fortran/0877/0877_0024.f90
- https://github.com/fujitsu/compiler-test-suite/blob/main/Fortran/0967/0967_0000.f90
- https://github.com/fujitsu/compiler-test-suite/blob/main/Fortran/0967/0967_0004.f90

Error:
```
flang -c 0839/0839_0000.f90 -fopenmp
error: Semantic errors in 0839/0839_0000.f90
./0839/0839_0000.f90:5:7: error: Trip count must be computable and invariant
!$omp do collapse(4)
^^
./0839/0839_0000.f90:16:7: error: Trip count must be computable and invariant
!$omp do collapse(4)
^^
```

Flang revision: `909f429b5e47aba3f67b4c1314974bd99c4483ef`

Is this an issue with flang or with the tests?