Revert "[hipblaslt] Fix WorkgroupMappingXCC alignment for 38-CU kernels (cherry-pick #5009) (#5144)" (#5398)

This reverts PR #5144 (merge commit
5236414).

## Reason for Revert

The release team for ROCm 7.2.1 has decided not to include the
WorkgroupMappingXCC alignment fix from PR #5144 and has requested that
it be reverted from the `release/rocm-rel-7.2` branch.

## What This Reverts

This revert undoes the changes made in PR #5144, which was a cherry-pick
of PR #5009 that fixed a performance regression in CPX Mode for AMD
Instinct GPUs with 38-CU partitions. The original fix adjusted the
WorkgroupMappingXCC parameter from 4 back to 1 for 38-CU configurations
in the gfx942_38cu library's YAML configuration files.

## Impact

After this revert, the WorkgroupMappingXCC values will return to their
pre-#5144 state (value of 4 for several key kernels), which may
reintroduce the performance regression in CPX Mode described in the
original PR.

Author: tony-davis