tests: Add FreeBSD image

The image is prepared following instructions as in:

https://wiki.qemu.org/Hosts/BSD

Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

tests/vm/freebsd

@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+#
+# FreeBSD VM image
+#
+# Copyright 2017 Red Hat Inc.
+#
+# Authors:
+#  Fam Zheng <famz@redhat.com>
+#
+# This code is licensed under the GPL version 2 or later.  See
+# the COPYING file in the top-level directory.
+#
+
+import os
+import sys
+import subprocess
+import basevm
+
+class FreeBSDVM(basevm.BaseVM):
+    name = "freebsd"
+    BUILD_SCRIPT = """
+        set -e;
+        cd $(mktemp -d /var/tmp/qemu-test.XXXXXX);
+        tar -xf /dev/vtbd1;
+        ./configure {configure_opts};
+        gmake -j{jobs};
+        gmake check;
+    """
+
+    def build_image(self, img):
+        cimg = self._download_with_cache("http://download.patchew.org/freebsd-11.1-amd64.img.xz",
+                sha256sum='adcb771549b37bc63826c501f05121a206ed3d9f55f49145908f7e1432d65891')
+        img_tmp_xz = img + ".tmp.xz"
+        img_tmp = img + ".tmp"
+        subprocess.check_call(["cp", "-f", cimg, img_tmp_xz])
+        subprocess.check_call(["xz", "-df", img_tmp_xz])
+        if os.path.exists(img):
+            os.remove(img)
+        os.rename(img_tmp, img)
+
+if __name__ == "__main__":
+    sys.exit(basevm.main(FreeBSDVM))