[clang-tools-extra] [Clang-Tidy] Add google-runtime-float Clang-Tidy check (PR #156763)

[Congcong Cai via cfe-commits]

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+.. title:: clang-tidy - google-runtime-float
+
+google-runtime-float
+====================
+
+Finds uses of ``long double`` and suggests replacing them with 64-bit
+or 128-bit floating-point types.
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HerrCai0907 wrote:

agree. I am also wondering what is the portable 128bit float?

https://github.com/llvm/llvm-project/pull/156763