KVM: x86: Fix uninitialized return code

This is a regression caused by 18595411a7.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b0b8abe..3bdaf298 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3006,6 +3006,7 @@
 		break;
 	}
 	case KVM_SET_LAPIC: {
+		r = -EINVAL;
 		if (!vcpu->arch.apic)
 			goto out;
 		u.lapic = memdup_user(argp, sizeof(*u.lapic));