#0: Remove exp+approx from exp

[VirdhatchaniKN]

Ticket

tenstorrent/tt-metal#27433 , tenstorrent/tt-metal#34061

Problem description

From here, exp+fast+approx is better compared to exp+approx .

What's changed

• Removed fast_and_approx flag as exp+approx is to be removed
• Created seperate init function specific to exp+approx(piecewise) that could be used for sdpa and other ops using the same
• init_exponential_sdpa_first_column is created specific for sdpa based on algorithm

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist

• All post commit CI passes
• Blackhole Post commit CI passes (if applicable)

[github-actions]

Thank you for your contribution! 🚀
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[fvranicTT]

Could you:

1. fix pre-commit issues (C++ code formatting)
2. create a branch in metal, fix the API breaking changes and run tests to make sure nothing remains broken.
3. link the metal PR here?

Thanks.