[llvm] [llvm-strings] Add --encoding={s,S,u} option (PR #221794)

[Harald van Dijk via llvm-commits]

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@@ -11,6 +11,10 @@ multiclass Eq<string name, string help> {
 
 def all : FF<"all", "Silently ignored. Present for GNU strings compatibility">;
 defm bytes : Eq<"bytes", "Print sequences of the specified length">;
+defm encoding : Eq<"encoding", [{Select the character encoding of the strings to find:
+s (ASCII characters)
+S (characters in the system's or user's character set)
+u (UTF-8 characters)}]>;
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hvdijk wrote:

I looked at the `--help` output when I had everything on one line and found it annoyingly difficult to read. I might be able to avoid that with much briefer `--help` output and just make sure that the complete descriptions are in the manpage.

https://github.com/llvm/llvm-project/pull/221794