incubator: fix javadoc directory removal

The directory for the javadoc was not removed recursively.

Change-Id: I6d7559eba0703700c4f3026c4b5d6b751057fec7
Signed-off-by: Geneviève Bastien <gbastien+lttng@versatic.net>
diff --git a/scripts/deploy-javadoc.sh b/scripts/deploy-javadoc.sh
index 2bc3d99..927f151 100755
--- a/scripts/deploy-javadoc.sh
+++ b/scripts/deploy-javadoc.sh
@@ -29,6 +29,6 @@
 fi
 
 $ECHO ${SSH} "mkdir -p ${JAVADOC_DESTINATION} && \
-              rm -f ${JAVADOC_DESTINATION}/${JAVADOC_REPO}"
+              rm -rf ${JAVADOC_DESTINATION}/${JAVADOC_REPO}"
 
 $ECHO $SCP -rv ${javadocPath} "${SSHUSER}:${JAVADOC_DESTINATION}"