lib.sh: redirect find errors to /dev/null

this silences confusing error messages that the user
sees on the screen, that are actually benign, and it
will thus reduce the number of people who ask questions
on #libreboot irc

Signed-off-by: Leah Rowe <leah@libreboot.org>

include/lib.sh

@@ -143,7 +143,8 @@ find_ex()
 	errx="$1" && shift 1
 	fd="`mktemp`" && x_ rm -f "$fd" && x_ touch "$fd"
 	xx="$1" && shift 1
-	$errx find "$@" | sort > "$fd" || $err "!find $(echo "$@") > \"$fd\""
+	$errx find "$@" 2>/dev/null | sort > "$fd" || \
+	    $err "!find $(echo "$@") > \"$fd\""
 	while read -r fx; do
 		"$xx" "$fx" || break; :
 	done < "$fd"