Add identify filter for ISO-8859-16 (Latin-10) encoding

Interestingly, it looks like the original author intended to add an identify filter
for this encoding, but never did so. The needed struct is there, but was never added
to the list of identify filters in mbfl_ident.c.

Author: alexdowad

ext/mbstring/libmbfl/mbfl/mbfl_ident.c

@@ -78,6 +78,7 @@
 #include "filters/mbfilter_iso8859_13.h"
 #include "filters/mbfilter_iso8859_14.h"
 #include "filters/mbfilter_iso8859_15.h"
+#include "filters/mbfilter_iso8859_16.h"
 #include "filters/mbfilter_base64.h"
 #include "filters/mbfilter_qprint.h"
 #include "filters/mbfilter_uuencode.h"
@@ -152,6 +153,7 @@ static const struct mbfl_identify_vtbl *mbfl_identify_filter_list[] = {
 	&vtbl_identify_8859_13,
 	&vtbl_identify_8859_14,
 	&vtbl_identify_8859_15,
+	&vtbl_identify_8859_16,
 	&vtbl_identify_armscii8,
 	&vtbl_identify_cp850,
 	&vtbl_identify_jis_ms,