./configure: export xfs config via --{enable, disable}-xfsctl

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
diff --git a/configure b/configure
index 9d5175b..69fb239 100755
--- a/configure
+++ b/configure
@@ -766,6 +766,10 @@
   ;;
   --enable-rbd) rbd="yes"
   ;;
+  --disable-xfsctl) xfs="no"
+  ;;
+  --enable-xfsctl) xfs="yes"
+  ;;
   --disable-smartcard) smartcard="no"
   ;;
   --enable-smartcard) smartcard="yes"