[clang] [llvm] [Clang] Cleanup docs and comments relating to -fextend-variable-liveness (PR #124767)

[Nick Desaulniers via cfe-commits]

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@@ -4352,19 +4352,11 @@ def stack_usage_file : Separate<["-"], "stack-usage-file">,
 def fextend_variable_liveness_EQ : Joined<["-"], "fextend-variable-liveness=">,
   Group<f_Group>, Visibility<[ClangOption, CC1Option]>,
   HelpText<"Extend the liveness of user variables through optimizations to "
-           "prevent stale or optimized-out variable values when debugging. Can "
-           "be applied to all user variables, or just to the C++ 'this' ptr. "
-           "May choose not to extend the liveness of some variables, such as "
-           "non-scalars larger than 4 unsigned ints, or variables in any "
-           "inlined functions.">,
+           "prevent stale or optimized-out variable values when debugging."
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nickdesaulniers wrote:

> I've fixed the build failure with https://github.com/llvm/llvm-project/commit/8578b816fa9050c33561f06d631459e12645953a.

Thanks!

https://github.com/llvm/llvm-project/pull/124767