qemu-ga: guest_file_handle_find(): take an Error argument Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com> *Fixed missing space character in error message Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>