Fix 'libgomp.c/pr122281.c' for non-USM offloading execution [PR122281]

Fix 'libgomp.c/pr122281.c' for non-USM offloading execution [PR122281]

... where it currently runs into:

    libgomp: cuCtxSynchronize error: an illegal memory access was encountered

... for nvptx, or similarly for GCN:

    Memory access fault by GPU node-1 (Agent handle: 0x34d77290) on address 0x7fff3c553000. Reason: Page not present or supervisor privilege.

Fix-up for commit r16-4961-ge2cbcd1b27c0da92bdcd96664064d3d0c1d44e6f
"Fix gimple_copy for OpenMP atomic load/store [PR122281, PR105001]".

	PR libgomp/122281
	libgomp/
	* testsuite/libgomp.c/pr122281.c: Fix for non-USM offloading
	execution.