qemu: Refactor qemuDomainSetVcpusFlags

This patch changes a switch statement into ifs when handling live vs.
configuration modifications getting rid of redundant code in case when
both live and persistent configuration gets changed.
(cherry picked from commit e99ad93d)

src/qemu/qemu_driver.c

@@ -3455,8 +3455,12 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
         goto endjob;
     }
 
-    switch (flags) {
-    case VIR_DOMAIN_AFFECT_CONFIG:
+    if (flags & VIR_DOMAIN_AFFECT_LIVE) {
+        if (qemudDomainHotplugVcpus(driver, vm, nvcpus) < 0)
+            goto endjob;
+    }
+
+    if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
         if (maximum) {
             persistentDef->maxvcpus = nvcpus;
             if (nvcpus < persistentDef->vcpus)
@@ -3464,24 +3468,12 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
         } else {
             persistentDef->vcpus = nvcpus;
         }
-        ret = 0;
-        break;
-
-    case VIR_DOMAIN_AFFECT_LIVE:
-        ret = qemudDomainHotplugVcpus(driver, vm, nvcpus);
-        break;
 
-    case VIR_DOMAIN_AFFECT_LIVE | VIR_DOMAIN_AFFECT_CONFIG:
-        ret = qemudDomainHotplugVcpus(driver, vm, nvcpus);
-        if (ret == 0) {
-            persistentDef->vcpus = nvcpus;
-        }
-        break;
+        if (virDomainSaveConfig(driver->configDir, persistentDef) < 0)
+            goto endjob;
     }
 
-    /* Save the persistent config to disk */
-    if (flags & VIR_DOMAIN_AFFECT_CONFIG)
-        ret = virDomainSaveConfig(driver->configDir, persistentDef);
+    ret = 0;
 
 endjob:
     if (qemuDomainObjEndJob(driver, vm) == 0)