tools: hv: vss: fix the write()'s argument: error -> vss_msg

tools: hv: vss: fix the write()'s argument: error -> vss_msg

Fix the write()'s argument in the daemon code.

Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit a689d2510f188e75391dbebacbddfd74d42f2a7e)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>