KVM: x86/mmu: Rename 'mask' to 'spte' in MMIO SPTE helpers

mainline inclusion
from mainline-v5.13-rc1
commit c236d962
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I7S3VQ
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c236d9623f7801e89a7b13e29df6709f0b216961



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The value returned by make_mmio_spte() is a SPTE, it is not a mask.
Name it accordingly.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210225204749.1512652-10-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>