[llvm] [OptTable] Make new lines in help text respect indentation (PR #75366)

[Fangrui Song via llvm-commits]

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@@ -50,6 +51,16 @@ def Blurmpq_eq : Flag<["--"], "blurmp=">;
 def Q : Flag<["-"], "Q">, Visibility<[SubtoolVis]>;
 def R : Flag<["-"], "R">, Visibility<[DefaultVis, SubtoolVis]>;
 
+def multiline_help : Flag<["-"], "multiline-help">, HelpText<"This a help text that has\nmultiple lines in it">, Visibility<[MultiLineVis]>;
+
+def multiline_help_long : 
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MaskRay wrote:

Delete trailing space on this line and the next line

https://github.com/llvm/llvm-project/pull/75366