[CPU][FP8] Support FP8 SDPA for CPU backend

[Valentine233]

Description:

1. Reuse the schema of qscaled_dot_product, and extend the FP8 dtype.
2. Support the fused attention and fallback math kernels for FP8 SDPA.
3. Support the pattern match for FP8 SDPA.

[pytorch-bot]

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[Valentine233]

@CaoE @jianan-gu Please help review, thanks~