KVM: x86: cleanup unused local variable

fix:
 arch/x86/kvm/x86.c: In function ‘handle_emulation_failure’:
 arch/x86/kvm/x86.c:3844: warning: unused variable ‘ctxt’
Signed-off-by: NXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

arch/x86/kvm/x86.c

@@ -3857,8 +3857,6 @@ static void inject_emulated_exception(struct kvm_vcpu *vcpu)
 
 static int handle_emulation_failure(struct kvm_vcpu *vcpu)
 {
-	struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
-
 	++vcpu->stat.insn_emulation_fail;
 	trace_kvm_emulate_insn_failed(vcpu);
 	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;