Revert 9434cb7d5e91718888489f8c08bfce7b768a7f1d

No need for that and it messes stuff. That refers to the localized document
charset, not the po.

man/po/po4a.cfg

@@ -4,7 +4,7 @@
 # Make sure the man pages are generated with the right encoding.
 [po4a_alias:man] man                                      \
                  opt_de:"-L ISO-8859-1"                   \
-                 opt_es:"-L UTF-8"                        \
+                 opt_es:"-L ISO-8859-1"                   \
                  opt_fr:"-L ISO-8859-1"                   \
                  opt_hu:"-L ISO-8859-2     -A ISO-8859-2" \
                  opt_ja:"-L euc-jp         -A utf-8"      \