* nr_mmu_pages would be non-zero only if kvm->arch.n_requested_mmu_pages is
  non-zero.

* nr_mmu_pages is always non-zero, since kvm_mmu_calculate_mmu_pages()
  never return zero.

Based on these two reasons, we can merge the two *if* clause and use the
return value from kvm_mmu_calculate_mmu_pages() directly. This simplify
the code and also eliminate the possibility for reader to believe
nr_mmu_pages would be zero.
Signed-off-by: NWei Yang <richard.weiyang@gmail.com>
Reviewed-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>