tpm: Clean up error reporting in tpm_init_tpmdev()

Calling error_report() in a function that takes an Error ** argument
is suspicious.  tpm_init_tpmdev() does that, and then fails without
setting an error.  Its caller main(), via tpm_init() and
qemu_opts_foreach(), is fine with it, but clean it up anyway.

Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20181017082702.5581-30-armbru@redhat.com>
diff --git a/tpm.c b/tpm.c
index 9303172..9c9e20b 100644
--- a/tpm.c
+++ b/tpm.c
@@ -89,19 +89,19 @@
     int i;
 
     if (!QLIST_EMPTY(&tpm_backends)) {
-        error_report("Only one TPM is allowed.");
+        error_setg(errp, "Only one TPM is allowed.");
         return 1;
     }
 
     id = qemu_opts_id(opts);
     if (id == NULL) {
-        error_report(QERR_MISSING_PARAMETER, "id");
+        error_setg(errp, QERR_MISSING_PARAMETER, "id");
         return 1;
     }
 
     value = qemu_opt_get(opts, "type");
     if (!value) {
-        error_report(QERR_MISSING_PARAMETER, "type");
+        error_setg(errp, QERR_MISSING_PARAMETER, "type");
         tpm_display_backend_drivers();
         return 1;
     }
@@ -109,8 +109,8 @@
     i = qapi_enum_parse(&TpmType_lookup, value, -1, NULL);
     be = i >= 0 ? tpm_be_find_by_type(i) : NULL;
     if (be == NULL) {
-        error_report(QERR_INVALID_PARAMETER_VALUE,
-                     "type", "a TPM backend type");
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
+                   "a TPM backend type");
         tpm_display_backend_drivers();
         return 1;
     }
@@ -118,7 +118,7 @@
     /* validate backend specific opts */
     qemu_opts_validate(opts, be->opts, &local_err);
     if (local_err) {
-        error_report_err(local_err);
+        error_propagate(errp, local_err);
         return 1;
     }
 
@@ -151,14 +151,10 @@
  * Initialize the TPM. Process the tpmdev command line options describing the
  * TPM backend.
  */
-int tpm_init(void)
+void tpm_init(void)
 {
-    if (qemu_opts_foreach(qemu_find_opts("tpmdev"),
-                          tpm_init_tpmdev, NULL, NULL)) {
-        return -1;
-    }
-
-    return 0;
+    qemu_opts_foreach(qemu_find_opts("tpmdev"),
+                      tpm_init_tpmdev, NULL, &error_fatal);
 }
 
 /*