Add validation for example 20

[neoblizz]

Fix the validation errors:

[Iris] [1/8] Validating...
[Iris] [7/8] Validating...
[Iris] [6/8] Validating...
[Iris] [4/8] Validating...
[Iris] [2/8] Validating...
[Iris] [1/8] Validating GEMM operation...
[Iris] [4/8] Validating GEMM operation...
[Iris] [7/8] Validating GEMM operation...
[Iris] [6/8] Validating GEMM operation...
[Iris] [2/8] Validating GEMM operation...
[Iris] [0/8] Validating...
[Iris] [0/8] Validating GEMM operation...
[Iris] [5/8] Validating...
[Iris] [5/8] Validating GEMM operation...
[Iris] [3/8] Validating...
[Iris] [3/8] Validating GEMM operation...
[Iris] [1/8] Max absolute difference: 508.0
[Iris] [4/8] Max absolute difference: 472.0
[Iris] [2/8] Max absolute difference: 508.0
[Iris] [0/8] GEMM validation passed.
[Iris] [7/8] Max absolute difference: 504.0
[Iris] [3/8] Max absolute difference: 504.0
[Iris] [5/8] Max absolute difference: 504.0
[Iris] [6/8] Max absolute difference: 490.0
[Iris] [1/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [4/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [2/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [7/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [5/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [3/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [1/8] GEMM validation failed.
[Iris] [4/8] GEMM validation failed.
[Iris] [2/8] GEMM validation failed.
[Iris] [7/8] GEMM validation failed.
[Iris] [6/8] Mismatch at index (0, 0): C=0.0, expected=192.0
[Iris] [5/8] GEMM validation failed.
[Iris] [3/8] GEMM validation failed.
[Iris] [6/8] GEMM validation failed.
[Iris] [6/8] Validating all-scatter operation...
[Iris] [3/8] Validating all-scatter operation...
[Iris] [5/8] Validating all-scatter operation...
[Iris] [4/8] Validating all-scatter operation...
[Iris] [2/8] Validating all-scatter operation...
[Iris] [7/8] Validating all-scatter operation...
[Iris] [1/8] Validating all-scatter operation...
[Iris] [0/8] Validating all-scatter operation...
[Iris] [7/8] All-scatter validation: Max absolute difference: 224.0
[Iris] [6/8] All-scatter validation: Max absolute difference: 241.0
[Iris] [4/8] All-scatter validation: Max absolute difference: 219.0
[Iris] [2/8] All-scatter validation: Max absolute difference: 220.0
[Iris] [3/8] All-scatter validation: Max absolute difference: 200.0
[Iris] [5/8] All-scatter validation: Max absolute difference: 235.0
[Iris] [2/8] All-scatter mismatch at rank 2 section, index (0, 0): got=-1.0234375, expected=3.0
[Iris] [2/8] All-scatter validation failed.
[Iris] [0/8] All-scatter validation passed.
[Iris] [2/8] Overall validation failed.
[Iris] [0/8] Overall validation passed.
[Iris] [3/8] All-scatter mismatch at rank 3 section, index (0, 0): got=-19.75, expected=4.0
[Iris] [3/8] All-scatter validation failed.
[Iris] [3/8] Overall validation failed.
[Iris] [4/8] All-scatter mismatch at rank 4 section, index (0, 0): got=-43.75, expected=5.0
[Iris] [5/8] All-scatter mismatch at rank 5 section, index (0, 0): got=82.0, expected=6.0
[Iris] [6/8] All-scatter mismatch at rank 6 section, index (0, 0): got=37.75, expected=7.0
[Iris] [4/8] All-scatter validation failed.
[Iris] [4/8] Overall validation failed.
[Iris] [5/8] All-scatter validation failed.
[Iris] [5/8] Overall validation failed.
[Iris] [1/8] All-scatter validation: Max absolute difference: 247.0
[Iris] [7/8] All-scatter mismatch at rank 7 section, index (0, 0): got=50.75, expected=8.0
[Iris] [6/8] All-scatter validation failed.
[Iris] [6/8] Overall validation failed.
[Iris] [7/8] All-scatter validation failed.
[Iris] [7/8] Overall validation failed.
[Iris] [1/8] All-scatter mismatch at rank 1 section, index (0, 0): got=26.625, expected=2.0
[Iris] [1/8] All-scatter validation failed.
[Iris] [1/8] Overall validation failed.
[Iris] [5/8] Validation completed
[Iris] [7/8] Validation completed
[Iris] [5/8] Benchmarking...
[Iris] [0/8] Validation completed
[Iris] [2/8] Validation completed
[Iris] [4/8] Validation completed
[Iris] [7/8] Benchmarking...
[Iris] [3/8] Validation completed
[Iris] [0/8] Benchmarking...
[Iris] [2/8] Benchmarking...
[Iris] [4/8] Benchmarking...
[Iris] [3/8] Benchmarking...
[Iris] [1/8] Validation completed
[Iris] [1/8] Benchmarking...
[Iris] [6/8] Validation completed
[Iris] [6/8] Benchmarking...
[Iris] [4/8] tile matmul + all_scatter (total_tiles=900): 1.449 ms  88.602 tflops
[Iris] [2/8] tile matmul + all_scatter (total_tiles=900): 1.446 ms  88.778 tflops
[Iris] [0/8] tile matmul + all_scatter (total_tiles=900): 1.448 ms  88.608 tflops
[Iris] [7/8] tile matmul + all_scatter (total_tiles=900): 1.452 ms  88.422 tflops
[Iris] [3/8] tile matmul + all_scatter (total_tiles=900): 1.447 ms  88.695 tflops
[Iris] [5/8] tile matmul + all_scatter (total_tiles=900): 1.453 ms  88.324 tflops
[Iris] [1/8] tile matmul + all_scatter (total_tiles=900): 1.446 ms  88.737 tflops
[Iris] [6/8] tile matmul + all_scatter (total_tiles=900): 1.446 ms  88.765 tflops