KVM: x86: Check that the high 32bits are clear in kvm_arch_vcpu_ioctl_run()

KVM: x86: Check that the high 32bits are clear in kvm_arch_vcpu_ioctl_run()

The "kvm_run->kvm_valid_regs" and "kvm_run->kvm_dirty_regs" variables are
u64 type.  We are only using the lowest 3 bits but we want to ensure that
the users are not passing invalid bits so that we can use the remaining
bits in the future.

However "sync_valid_fields" and kvm_sync_valid_fields() are u32 type so
the check only ensures that the lower 32 bits are clear.  Fix this by
changing the types to u64.

Fixes: 74c1807f6c4f ("KVM: x86: block KVM_CAP_SYNC_REGS if guest state is protected")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/ec25aad1-113e-4c6e-8941-43d432251398@stanley.mountain
Signed-off-by: Sean Christopherson <seanjc@google.com>