OpenMP GPU support for Array sections in map clause

[naromero77]

This is more of a question than an actual bug. (In line with https://github.com/flang-compiler/flang/issues/867).

I am trying to compile some OpenMP target (4.5) code. Much of it compiles, but then I get to this warning repeatedly: F90-W-1206-OpenMP GPU - Array sections in "map" clause is not implemented yet, the entire array will be mapped (../rte/kernels-openacc/mo_optical_props_kernels.F90: 62)

Again, I would re-iterate how badly a functional Fortran compiler with OpenMP target support is needed by the community.