configure: Remove -lxencall for Xen detection

QEMU does not depends on libxencall, it was added because it was a
missing link dependency of libxendevicemodel, but now the later should
be built properly.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
diff --git a/configure b/configure
index 57b5ae6..139638e 100755
--- a/configure
+++ b/configure
@@ -2015,7 +2015,7 @@
   else
 
     xen_libs="-lxenstore -lxenctrl -lxenguest"
-    xen_stable_libs="-lxencall -lxenforeignmemory -lxengnttab -lxenevtchn"
+    xen_stable_libs="-lxenforeignmemory -lxengnttab -lxenevtchn"
 
     # First we test whether Xen headers and libraries are available.
     # If no, we are done and there is no Xen support.