patch 8.2.4380: small differences between Chinese translation files

Problem:    Small differences between Chinese translation files.
Solution:   Add rule for converting UTF-8 to gb2312. (closes #9773)
diff --git a/src/po/Make_all.mak b/src/po/Make_all.mak
index b062bcc..8f28dfa 100644
--- a/src/po/Make_all.mak
+++ b/src/po/Make_all.mak
@@ -134,6 +134,7 @@
 		ru.cp1251.mo \
 		sk.cp1250.mo \
 		uk.cp1251.mo \
+		zh_CN.mo \
 		zh_CN.cp936.mo \