Drop skip_mmu_sync and skip_tlb_flush from __kvm_mmu_new_pgd() now that
all call sites unconditionally skip both the sync and flush.

No functional change intended.
Signed-off-by: NSean Christopherson <seanjc@google.com>
Message-Id: <20210609234235.1244004-8-seanjc@google.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>