[CK] Workaround blockscale wp test failure (#4372)

## Motivation

Workaround to fix blockscale wp test failure for pipeline v3

## Technical Details

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## Test Plan

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## Test Result

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## Submission Checklist

- [ ] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

include/ck/tensor_operation/gpu/block/blockwise_gemm_pipeline_xdlops_blockscale_b_preshuffle_v3.hpp

@@ -704,10 +704,12 @@ struct BlockwiseGemmXdlops_pipeline_blockscale_bpreshuffle_v3<BlockGemmPipelineS
                             });
                         });
 
-                        // We have to 1 stage early sync the lds for workaround the compiler
-                        // limitation
-                        if constexpr(m0.value == (MRepeat - LocalPrefetchStages - 1))
+                        // Compiler issue. Previously the sync was done one stage earlier to fix it.
+                        // Problem shows up again with latest compiler so we sync at the correct
+                        // iteration and then we force the instructions before the sync
+                        if constexpr(m0.value == (MRepeat - LocalPrefetchStages))
                         {
+                            __builtin_amdgcn_sched_barrier(0); // force all instructions before this
                             block_sync_lds();
                         }
 
@@ -833,6 +835,7 @@ struct BlockwiseGemmXdlops_pipeline_blockscale_bpreshuffle_v3<BlockGemmPipelineS
 
                 if constexpr(m0.value == (MRepeat - LocalPrefetchStages))
                 {
+                    __builtin_amdgcn_sched_barrier(0); // force all instructions before this
                     block_sync_lds();
                 }