qemu-common.h: Make qemu_init_vcpu() stub static inline

Turn the *-user macro into a no-op inline function to avoid
unused-variable warnings and band-aiding #ifdef'ery.

This allows to drop an #ifdef for alpha and avoids more for unicore32
and other upcoming trivial realizefn implementations.
Suggested-by: NLluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>
Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>

include/qemu-common.h

@@ -288,7 +288,9 @@ struct qemu_work_item {
 };
 
 #ifdef CONFIG_USER_ONLY
-#define qemu_init_vcpu(env) do { } while (0)
+static inline void qemu_init_vcpu(void *env)
+{
+}
 #else
 void qemu_init_vcpu(void *env);
 #endif

target-alpha/cpu.c

@@ -26,11 +26,9 @@
 
 static void alpha_cpu_realize(Object *obj, Error **errp)
 {
-#ifndef CONFIG_USER_ONLY
     AlphaCPU *cpu = ALPHA_CPU(obj);
 
     qemu_init_vcpu(&cpu->env);
-#endif
 }
 
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