KVM: MMU: use page table level macro

Its much cleaner to use PT_PAGE_TABLE_LEVEL than its numeric value.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 29ad6f9..07424cf 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3618,7 +3618,7 @@
 	 * Skip write-flooding detected for the sp whose level is 1, because
 	 * it can become unsync, then the guest page is not write-protected.
 	 */
-	if (sp->role.level == 1)
+	if (sp->role.level == PT_PAGE_TABLE_LEVEL)
 		return false;
 
 	return ++sp->write_flooding_count >= 3;