Documentation: installed man pages don't need to be executable

Install the man pages with mode 644 instead of 755
Signed-off-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/DocBook/Makefile

@@ -60,7 +60,7 @@ mandocs: $(MAN)
 
 installmandocs: mandocs
 	mkdir -p /usr/local/man/man9/
-	install $(obj)/man/*.9.gz /usr/local/man/man9/
+	install -m 644 $(obj)/man/*.9.gz /usr/local/man/man9/
 
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 #External programs used