[llvm] [llvm-cxxfilt] update docs to reflect #106233 (PR #165709)

[Mads Marquart via llvm-commits]

https://github.com/madsmtm created https://github.com/llvm/llvm-project/pull/165709

It looks like the documentation for `llvm-cxxfilt`'s `--[no-]strip-underscore` options weren't updated when https://github.com/llvm/llvm-project/pull/106233 was made.

CC @Michael137 (I don't have merge rights myself).

>From 6cdf11c03a1ef165e98020b4b346db599cd2d1c2 Mon Sep 17 00:00:00 2001
From: Mads Marquart <mads at marquart.dk>
Date: Thu, 30 Oct 2025 13:03:37 +0100
Subject: [PATCH] [llvm-cxxfilt] update docs to reflect 30f2319

---
 llvm/docs/CommandGuide/llvm-cxxfilt.rst | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/llvm/docs/CommandGuide/llvm-cxxfilt.rst b/llvm/docs/CommandGuide/llvm-cxxfilt.rst
index 8c61cedd9b70b..8e509cec6ce02 100644
--- a/llvm/docs/CommandGuide/llvm-cxxfilt.rst
+++ b/llvm/docs/CommandGuide/llvm-cxxfilt.rst
@@ -54,8 +54,7 @@ OPTIONS
 
 .. option:: --no-strip-underscore, -n
 
-  Do not strip a leading underscore. This is the default for all platforms
-  except Mach-O based hosts.
+  Do not strip a leading underscore. This is the default for all platforms.
 
 .. option:: --quote
 
@@ -64,7 +63,7 @@ OPTIONS
 .. option:: --strip-underscore, -_
 
   Strip a single leading underscore, if present, from each input name before
-  demangling. On by default on Mach-O based platforms.
+  demangling.
 
 .. option:: --types, -t