Convert ssh2 check to use LIBVIRT_CHECK_PKG

This converts the libssh2 configure check to use LIBVIRT_CHECK_PKG.
Previously it would check version 1.0 and 1.3, but this simplifies
things to just require version 1.3

m4/virt-ssh2.m4

@@ -0,0 +1,26 @@
+dnl The libssh2.so library
+dnl
+dnl Copyright (C) 2012-2013 Red Hat, Inc.
+dnl
+dnl This library is free software; you can redistribute it and/or
+dnl modify it under the terms of the GNU Lesser General Public
+dnl License as published by the Free Software Foundation; either
+dnl version 2.1 of the License, or (at your option) any later version.
+dnl
+dnl This library is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+dnl Lesser General Public License for more details.
+dnl
+dnl You should have received a copy of the GNU Lesser General Public
+dnl License along with this library.  If not, see
+dnl <http://www.gnu.org/licenses/>.
+dnl
+
+AC_DEFUN([LIBVIRT_CHECK_SSH2],[
+  LIBVIRT_CHECK_PKG([SSH2], [libssh2], [1.3])
+])
+
+AC_DEFUN([LIBVIRT_RESULT_SSH2],[
+  LIBVIRT_RESULT_LIB([SSH2])
+])