Add fix for CVE-2020-25713 raptor2: malformed input file segfault

The sample file in the upstream bug report from the PR causes a
bus error in PORTREVISION 16, and returns an error (as I suppose
it should) now.

PR:		251102
Reported by:	pi
Obtained from:	upstream

textproc/raptor2/Makefile

@@ -3,7 +3,7 @@
 
 PORTNAME=	raptor2
 PORTVERSION=	2.0.15
-PORTREVISION=	16
+PORTREVISION=	17
 CATEGORIES=	textproc
 MASTER_SITES=	http://download.librdf.org/source/ \
 		SF/librdf/${PORTNAME}/${PORTVERSION}

textproc/raptor2/files/patch-CVE-2020-25713

@@ -0,0 +1,33 @@
+From a549457461874157c8c8e8e8a6e0eec06da4fbd0 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Caol=C3=A1n=20McNamara?= <caolanm@redhat.com>
+Date: Tue, 24 Nov 2020 10:30:20 +0000
+Subject: [PATCH] CVE-2020-25713 raptor2: malformed input file can lead to a
+ segfault
+
+due to an out of bounds array access in
+raptor_xml_writer_start_element_common
+
+See:
+https://bugs.mageia.org/show_bug.cgi?id=27605
+https://www.openwall.com/lists/oss-security/2020/11/13/1
+https://gerrit.libreoffice.org/c/core/+/106249
+---
+ src/raptor_xml_writer.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/raptor_xml_writer.c b/src/raptor_xml_writer.c
+index 56993dc3..4426d38c 100644
+--- src/raptor_xml_writer.c
++++ src/raptor_xml_writer.c
+@@ -227,7 +227,7 @@ raptor_xml_writer_start_element_common(raptor_xml_writer* xml_writer,
+           
+           /* check it wasn't an earlier declaration too */
+           for(j = 0; j < nspace_declarations_count; j++)
+-            if(nspace_declarations[j].nspace == element->attributes[j]->nspace) {
++            if(nspace_declarations[j].nspace == element->attributes[i]->nspace) {
+               declare_me = 0;
+               break;
+             }
+-- 
+2.28.0
+