kvm: reduce code duplication in config_iothread

We have some duplicated code in the CONFIG_IOTHREAD #ifdef and #else
cases. Fix that.
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

kvm-all.c

@@ -935,14 +935,11 @@ void kvm_setup_guest_memory(void *start, size_t size)
 static void on_vcpu(CPUState *env, void (*func)(void *data), void *data)
 {
 #ifdef CONFIG_IOTHREAD
-    if (env == cpu_single_env) {
-        func(data);
-        return;
+    if (env != cpu_single_env) {
+        abort();
     }
-    abort();
-#else
-    func(data);
 #endif
+    func(data);
 }
 
 struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *env,