tpm: remove init() class method

No backend use it.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NStefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

backends/tpm.c

@@ -47,13 +47,11 @@ enum TpmType tpm_backend_get_type(TPMBackend *s)
 int tpm_backend_init(TPMBackend *s, TPMState *state,
                      TPMRecvDataCB *datacb)
 {
-    TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s);
-
     s->tpm_state = state;
     s->recv_data_callback = datacb;
     s->had_startup_error = false;
 
-    return k->init ? k->init(s) : 0;
+    return 0;
 }
 
 int tpm_backend_startup_tpm(TPMBackend *s)

include/sysemu/tpm_backend.h

@@ -66,8 +66,6 @@ struct TPMBackendClass {
 
     TPMBackend *(*create)(QemuOpts *opts, const char *id);
 
-    /* initialize the backend */
-    int (*init)(TPMBackend *t);
     /* start up the TPM on the backend */
     int (*startup_tpm)(TPMBackend *t);