Fix Distance.cu bitset idx match

[kayang-potato]

When running a batch, the bitset match is incorrect.

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[mergify]

@kayang-potato Please associate the related issue to the body of your Pull Request. (eg. “issue: #”)

[cydrain]

Hi @kayang-potato ,
By now knowhere only supports RAFT GPU index, Faiss GPU index has not been compiled in knowhere.
How did you find this issue ?

[cydrain]

/hold

[kayang-potato]

Hi @kayang-potato , By now knowhere only supports RAFT GPU index, Faiss GPU index has not been compiled in knowhere. How did you find this issue ?

您好，这张CMakelists中表明除了RAFT GPU index，knowhere还编译了Flat GPU，而该索引search的底层调用了thirdparty/faiss/faiss/gpu/impl/Distance.cu的runDistance函数，该函数错误地使用了bitset，麻烦再关注一下，感谢！

[cydrain]

Hi @kayang-potato , By now knowhere only supports RAFT GPU index, Faiss GPU index has not been compiled in knowhere. How did you find this issue ?

您好，这张CMakelists中表明除了RAFT GPU index，knowhere还编译了Flat GPU，而该索引search的底层调用了thirdparty/faiss/faiss/gpu/impl/Distance.cu的runDistance函数，该函数错误地使用了bitset，麻烦再关注一下，感谢！

The line 108 means, removing ${KNOWHERE_GPU_SRCS} from ${KNOWHERE_SRCS}