vmx: refine validity check for guest linear address

The validity check for the guest line address is inefficient,
check the invalid value instead of enumerating the valid ones.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 5cede40..8d28804 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6109,7 +6109,7 @@
 	exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
 
 	gla_validity = (exit_qualification >> 7) & 0x3;
-	if (gla_validity != 0x3 && gla_validity != 0x1 && gla_validity != 0) {
+	if (gla_validity == 0x2) {
 		printk(KERN_ERR "EPT: Handling EPT violation failed!\n");
 		printk(KERN_ERR "EPT: GPA: 0x%lx, GVA: 0x%lx\n",
 			(long unsigned int)vmcs_read64(GUEST_PHYSICAL_ADDRESS),