KVM: x86/MMU: Simplify flow of vmx_get_mt_mask

Remove the gotos from vmx_get_mt_mask.  It's easier to build the whole
memory type at once, than it is to combine separate cacheability and
ipat fields.

No functional change intended.

Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211115234603.2908381-12-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>