libgomp: Fix up target-31.c test [PR106045]

libgomp: Fix up target-31.c test [PR106045]

The i variable is used inside of the parallel in:
      #pragma omp simd safelen(32) private (v)
      for (i = 0; i < 64; i++)
        {
          v = 3 * i;
          ll[i] = u1 + v * u2[0] + u2[1] + x + y[0] + y[1] + v + h[0] + u3[i];
        }
where i is predetermined linear (so while inside of the body
it is safe, private per SIMD lane var) the final value is written to
the shared variable, and in:
      for (i = 0; i < 64; i++)
        if (ll[i] != u1 + 3 * i * u2[0] + u2[1] + x + y[0] + y[1] + 3 * i + 13 + 14 + i)
          #pragma omp atomic write
            err = 1;
which is a normal loop and so it isn't in any way privatized there.
So we have a data race, fixed by adding private (i) clause to the
parallel.

2022-06-21  Jakub Jelinek  <jakub@redhat.com>
	    Paul Iannetta  <piannetta@kalrayinc.com>

	PR libgomp/106045
	* testsuite/libgomp.c/target-31.c: Add private (i) clause.