RISC-V: KVM: add __init annotation to riscv_kvm_init()

The riscv_kvm_init() is a module_init entry so let us add __init
annotation to it.
Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Anup Patel <anup@brainfault.org>

arch/riscv/kvm/main.c

@@ -122,7 +122,7 @@ void kvm_arch_exit(void)
 {
 }
 
-static int riscv_kvm_init(void)
+static int __init riscv_kvm_init(void)
 {
 	return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
 }