KVM: Trivial: Remove unused struct cpu_user_regs declaration

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>

drivers/kvm/x86_emulate.h

@@ -112,8 +112,6 @@ struct x86_emulate_ops {
 
 };
 
-struct cpu_user_regs;
-
 struct x86_emulate_ctxt {
 	/* Register state before/after emulation. */
 	struct kvm_vcpu *vcpu;