generate-cmdlist.sh: trivial whitespace change

Add " " before a "|" at the end of a line in generate-cmdlist.sh for
consistency with other code in the file. Some of the surrounding code
will be modified in subsequent commits.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

generate-cmdlist.sh

@@ -10,7 +10,7 @@ command_list () {
 }
 
 get_categories () {
-	tr ' ' '\012'|
+	tr ' ' '\012' |
 	grep -v '^$' |
 	sort |
 	uniq