b=114353, r=yokoyama, sr=jst, a=asa

fix for nsUNIXCharset.cpp assertions and
startup failure on FreeBSD

--pete

intl/uconv/src/unixcharset.properties

@@ -172,6 +172,8 @@ locale.all.en_TW.IBM-eucTW=x-euc-tw
 locale.all.en_US=ISO-8859-1
 locale.all.en_US.88591=ISO-8859-1
 locale.all.en_US.ISO8859-1=ISO-8859-1
+#FreeBSD
+locale.all.en_US.ISO_8859-1=ISO-8859-1
 # Solaris
 locale.all.en_US.UTF-8=UTF-8
 # Solaris