[OMP] Restore 'omp declare target link' handling

    PASS: libgomp.c/target-link-1.c (test for excess errors)
    [-PASS:-]{+FAIL:+} libgomp.c/target-link-1.c execution test

We need to revert one line of code change from r279625.

	libgomp/
	* target.c (gomp_map_vars_internal): Restore 'omp declare target
	link' handling.

From-SVN: r279701

libgomp/ChangeLog

+2019-12-21  Thomas Schwinge  <thomas@codesourcery.com>
+
+	* target.c (gomp_map_vars_internal): Restore 'omp declare target
+	link' handling.
+
 2019-12-19  Julian Brown  <julian@codesourcery.com>
 
 	* testsuite/libgomp.oacc-fortran/class-ptr-param.f95: New test.

libgomp/target.c

@@ -1129,7 +1129,6 @@ gomp_map_vars_internal (struct gomp_device_descr *devicep,
 		tgt->list[i].length = k->host_end - k->host_start;
 		k->refcount = 1;
 		k->virtual_refcount = 0;
-		k->aux = NULL;
 		tgt->refcount++;
 		array->left = NULL;
 		array->right = NULL;