chapter06: fix a stupid error in po file

zh_CN/chapter06/chapter06.po

@@ -17,5 +17,5 @@ msgstr ""
 
 #. type: Content of: <chapter><title>
 #: /home/xry111/svn-repos/LFS-BOOK/chapter06/chapter06.xml:12
-msgid "交叉编译临时工具"
-msgstr ""
+msgid "Cross Compiling Temporary Tools"
+msgstr "交叉编译临时工具"