target/arm: move kvm stubs and remove CONFIG_KVM from kvm_arm.h

Add a forward decl for struct kvm_vcpu_init to avoid pulling all kvm
headers.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250512180502.2395029-5-pierrick.bouvier@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm/kvm-stub.c

@@ -22,3 +22,80 @@ bool write_list_to_kvmstate(ARMCPU *cpu, int level)
 {
     g_assert_not_reached();
 }
+
+/*
+ * It's safe to call these functions without KVM support.
+ * They should either do nothing or return "not supported".
+ */
+bool kvm_arm_aarch32_supported(void)
+{
+    return false;
+}
+
+bool kvm_arm_pmu_supported(void)
+{
+    return false;
+}
+
+bool kvm_arm_sve_supported(void)
+{
+    return false;
+}
+
+bool kvm_arm_mte_supported(void)
+{
+    return false;
+}
+
+/*
+ * These functions should never actually be called without KVM support.
+ */
+void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_add_vcpu_properties(ARMCPU *cpu)
+{
+    g_assert_not_reached();
+}
+
+int kvm_arm_get_max_vm_ipa_size(MachineState *ms, bool *fixed_ipa)
+{
+    g_assert_not_reached();
+}
+
+int kvm_arm_vgic_probe(void)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_pmu_set_irq(ARMCPU *cpu, int irq)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_pmu_init(ARMCPU *cpu)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_pvtime_init(ARMCPU *cpu, uint64_t ipa)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)
+{
+    g_assert_not_reached();
+}
+
+uint32_t kvm_arm_sve_get_vls(ARMCPU *cpu)
+{
+    g_assert_not_reached();
+}
+
+void kvm_arm_enable_mte(Object *cpuobj, Error **errp)
+{
+    g_assert_not_reached();
+}