qemuDomainDetachDeviceLiveAndConfig: Avoid overwriting @ret

The fact that we are overwriting @ret multiple times makes it
difficult to see what is actually happening here. Follow our
traditional pattern where @ret is initialized to -1, and set to 0
only in case we know we succeeded.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

src/qemu/qemu_driver.c

@@ -8710,35 +8710,35 @@ qemuDomainDetachDeviceLiveAndConfig(virQEMUDriverPtr driver,
         if (!vmdef)
             goto cleanup;
 
-        if ((ret = qemuDomainDetachDeviceConfig(vmdef, dev, caps,
-                                                parse_flags,
-                                                driver->xmlopt)) < 0)
+        if (qemuDomainDetachDeviceConfig(vmdef, dev, caps,
+                                         parse_flags,
+                                         driver->xmlopt) < 0)
             goto cleanup;
     }
 
     if (flags & VIR_DOMAIN_AFFECT_LIVE) {
-        if ((ret = qemuDomainDetachDeviceLive(vm, dev_copy, driver)) < 0)
+        if (qemuDomainDetachDeviceLive(vm, dev_copy, driver) < 0)
             goto cleanup;
         /*
          * update domain status forcibly because the domain status may be
          * changed even if we failed to attach the device. For example,
          * a new controller may be created.
          */
-        if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, caps) < 0) {
-            ret = -1;
+        if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm, caps) < 0)
             goto cleanup;
-        }
     }
 
     /* Finally, if no error until here, we can save config. */
     if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
-        ret = virDomainSaveConfig(cfg->configDir, caps, vmdef);
-        if (!ret) {
-            virDomainObjAssignDef(vm, vmdef, false, NULL);
-            vmdef = NULL;
-        }
+        if (virDomainSaveConfig(cfg->configDir, caps, vmdef) < 0)
+            goto cleanup;
+
+        virDomainObjAssignDef(vm, vmdef, false, NULL);
+        vmdef = NULL;
     }
 
+    ret = 0;
+
  cleanup:
     virObjectUnref(caps);
     virObjectUnref(cfg);