Fix some regressions caused by r369553 on old versions of Debian and Ubuntu
It was causing some errors like:

Encoding error:
'ascii' codec can't decode byte 0xe2 in position 341: ordinal not in range(128)
The full traceback has been saved in /tmp/sphinx-err-y2fq4dtb.log, if you want to report the issue to the developers.

llvm-svn: 369644
diff --git a/llvm/docs/CommandGuide/llvm-strings.rst b/llvm/docs/CommandGuide/llvm-strings.rst
index d8ab9cb..f6307d4 100644
--- a/llvm/docs/CommandGuide/llvm-strings.rst
+++ b/llvm/docs/CommandGuide/llvm-strings.rst
@@ -12,4 +12,4 @@
 -----------
 
 :program:`llvm-strings` is a tool that prints strings in files. The goal is to
-make it a drop-in replacement for GNU’s :program:`strings`.
+make it a drop-in replacement for GNU's :program:`strings`.