KVM: VMX: Rename pt_desc.addr_range to pt_desc.num_address_ranges

To better self explain the meaning of this field and match the
PT_CAP_num_address_ranges constatn.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20210827070249.924633-4-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>