Fix up 'libgomp.oacc-fortran/print-1.f90' GCN offloading compilation [PR104717]

That got broken by recent commit b2202431
"fortran: Fix up gfc_trans_oacc_construct [PR104717]".

	PR fortran/104717
	libgomp/
	* testsuite/libgomp.oacc-fortran/print-1.f90: Add OpenACC
	privatization scanning.  For GCN offloading compilation, raise
	'-mgang-private-size'.