locking: Add io_timeout to sanlock

https://bugzilla.redhat.com/show_bug.cgi?id=1251190

So, if domain loses access to storage, sanlock tries to kill it
after some timeout. So far, the default is 80 seconds. But for
some scenarios this might not be enough. We should allow users to
adjust the timeout according to their needs.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

m4/virt-sanlock.m4

@@ -46,6 +46,13 @@ AC_DEFUN([LIBVIRT_CHECK_SANLOCK],[
         [whether sanlock supports sanlock_inq_lockspace])
     fi
 
+    AC_CHECK_LIB([sanlock_client], [sanlock_add_lockspace_timeout],
+                 [sanlock_add_lockspace_timeout=yes], [sanlock_add_lockspace_timeout=no])
+    if test "x$sanlock_add_lockspace_timeout" = "xyes" ; then
+      AC_DEFINE_UNQUOTED([HAVE_SANLOCK_ADD_LOCKSPACE_TIMEOUT], 1,
+        [whether Sanlock supports sanlock_add_lockspace_timeout])
+    fi
+
     CPPFLAGS="$old_cppflags"
     LIBS="$old_libs"
   fi