rest: the "data" field of results might not be there
rest: the "data" field of results might not be there

For PATCH requests, for example, the user might be changing other fields
only.  Check whether the field is there before accessing it.

Reviewed-by: Caio Carrara <b2e41b6a3a746570c14a7688e6a5d56f0036cfa7@redhat.com>
Signed-off-by: Paolo Bonzini <69d3ebcf5ee4e7f05a50dc23cd96655b730804b4@redhat.com>

patchew-project/patchew,patchew-project/patchew,patchew-project/patchew,patchew-project/patchew