openacc: Don't strip TO_PSET/POINTER for enter/exit data

openacc: Don't strip TO_PSET/POINTER for enter/exit data

OpenACC 2.6 specifies that the array descriptor (when present) must be
copied to the target before attaching pointers in Fortran. This patch
reverses the stripping of GOMP_MAP_TO_PSET and GOMP_MAP_POINTER that
was introduced by the "OpenACC reference count overhaul" patch.

2020-07-10  Julian Brown  <julian@codesourcery.com>
	    Thomas Schwinge  <thomas@codesourcery.com>

gcc/
	* gimplify.c (gimplify_scan_omp_clauses): Do not strip
	GOMP_MAP_TO_PSET/GOMP_MAP_POINTER for OpenACC enter/exit data
	directives (see also PR92929).

gcc/testsuite/
	* gfortran.dg/goacc/finalize-1.f: Update expected dump output.

libgomp/
	* testsuite/libgomp.oacc-fortran/dynamic-pointer-1.f90: New test.

Co-Authored-By: Thomas Schwinge <thomas@codesourcery.com>
(cherry picked from commit b20097c65d2e74b1901fba1c55c77f0407e542d2)