PR85463 '[nvptx] "exit" in offloaded region doesn't terminate process'

PR85463 '[nvptx] "exit" in offloaded region doesn't terminate process'

	libgomp/
	PR libfortran/85166
	* testsuite/libgomp.oacc-fortran/abort-1.f90: Switch back to "call
	abort".
	* testsuite/libgomp.oacc-fortran/abort-2.f90: Likewise.

	libgfortran/
	PR libfortran/85166
	PR libgomp/85463
	* runtime/minimal.c (stop_numeric): Reimplement.
	(stop_string, error_stop_string, error_stop_numeric): New
	functions.
	libgomp/
	PR libgomp/85463
	* testsuite/libgomp.oacc-fortran/error_stop-1.f: New file.
	* testsuite/libgomp.oacc-fortran/error_stop-2.f: Likewise.
	* testsuite/libgomp.oacc-fortran/error_stop-3.f: Likewise.
	* testsuite/libgomp.oacc-fortran/stop-1.f: Likewise.
	* testsuite/libgomp.oacc-fortran/stop-2.f: Likewise.
	* testsuite/libgomp.oacc-fortran/stop-3.f: Likewise.

From-SVN: r259491