tpm: Convert to new qapi union layout

We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

Make the conversion to the new layout for TPM-related code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-22-git-send-email-eblake@redhat.com>
[Commit message tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

hmp.c

@@ -841,11 +841,11 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
                        c, TpmModel_lookup[ti->model]);
 
         monitor_printf(mon, "  \\ %s: type=%s",
-                       ti->id, TpmTypeOptionsKind_lookup[ti->options->kind]);
+                       ti->id, TpmTypeOptionsKind_lookup[ti->options->type]);
 
-        switch (ti->options->kind) {
+        switch (ti->options->type) {
         case TPM_TYPE_OPTIONS_KIND_PASSTHROUGH:
-            tpo = ti->options->passthrough;
+            tpo = ti->options->u.passthrough;
             monitor_printf(mon, "%s%s%s%s",
                            tpo->has_path ? ",path=" : "",
                            tpo->has_path ? tpo->path : "",

tpm.c

@@ -260,9 +260,9 @@ static TPMInfo *qmp_query_tpm_inst(TPMBackend *drv)
 
     switch (drv->ops->type) {
     case TPM_TYPE_PASSTHROUGH:
-        res->options->kind = TPM_TYPE_OPTIONS_KIND_PASSTHROUGH;
+        res->options->type = TPM_TYPE_OPTIONS_KIND_PASSTHROUGH;
         tpo = g_new0(TPMPassthroughOptions, 1);
-        res->options->passthrough = tpo;
+        res->options->u.passthrough = tpo;
         if (drv->path) {
             tpo->path = g_strdup(drv->path);
             tpo->has_path = true;