KVM: MMU: Track NX state in struct kvm_mmu

With Nested Paging emulation the NX state between the two
MMU contexts may differ. To make sure that always the right
fault error code is recorded this patch moves the NX state
into struct kvm_mmu so that the code can distinguish between
L1 and L2 NX state.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index bd59b48..b43686a 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -259,6 +259,8 @@
 	u64 *lm_root;
 	u64 rsvd_bits_mask[2][4];
 
+	bool nx;
+
 	u64 pdptrs[4]; /* pae */
 };