Removed unused/unresolvable XSL reference that breaks FireFox load of RDF.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/branches/fop-1_1@1357045 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/doap.rdf

@@ -15,7 +15,6 @@
   See the License for the specific language governing permissions and
   limitations under the License.
 -->
-<?xml-stylesheet type="text/xsl" href="../xsl/p2.xsl"?>
 <rdf:RDF xml:lang="en"
          xmlns="http://usefulinc.com/ns/doap#" 
          xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"