KVM: MMU: pass unadulterated gpa to direct_page_fault

Do not bother removing the low bits of the gpa.  This masking dates back
to the very first commit of KVM but it is unnecessary, as exemplified
by the other call in kvm_tdp_page_fault.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu/mmu.c

@@ -4018,7 +4018,7 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa,
 	pgprintk("%s: gva %lx error %x\n", __func__, gpa, error_code);
 
 	/* This path builds a PAE pagetable, we can map 2mb pages at maximum. */
-	return direct_page_fault(vcpu, gpa & PAGE_MASK, error_code, prefault,
+	return direct_page_fault(vcpu, gpa, error_code, prefault,
 				 PG_LEVEL_2M, false);
 }