fix asymmetric in dequantize (#7283)
框架中反量化算子（dequantize）在非对称量化产生结果时只将float类型转成half类型，漏掉了对float类型的转换，导致在输出是float类型时，会产生精度误差。
<img width="809" alt="企业微信截图_1747294273387"
src="https://github.com/user-attachments/assets/3be19f06-89fe-404c-bc32-efcacc31bb1d"
/>
---------
Co-authored-by: 潘俊涵 <sp.junhan.pan@enflame-tech.com>
Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>
Co-authored-by: Olatunji Ruwase <tunji.ruwase@snowflake.com>
Co-authored-by: Zhipeng Wang <zhipeng.rainbowserie@gmail.com>
