[clang] [compiler-rt] [UBSan] Add check that detects division by zero for fixed-point types (PR #165181)

[Vitaly Buka via cfe-commits]

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@@ -224,6 +226,8 @@ You can also use the following check groups:
      ``nullability-*`` group of checks.
   -  ``-fsanitize=undefined-trap``: Deprecated alias of
      ``-fsanitize=undefined``.
+  -  ``-fsanitize=fixed-point``: Checks for undefined behavior with fixed point
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vitalybuka wrote:

the group is alias to help flip multiple checks.
A group of 1 check is redundant, even 2  probably to low for own group


https://github.com/llvm/llvm-project/pull/165181