KVM: VMX: Remove defunct "nr_active_uret_msrs" field

Remove vcpu_vmx.nr_active_uret_msrs and its associated comment, which are
both defunct now that KVM keeps the list constant and instead explicitly
tracks which entries need to be loaded into hardware.

No functional change intended.

Fixes: ee9d22e0 ("KVM: VMX: Use flag to indicate "active" uret MSRs instead of sorting list")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210908002401.1947049-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/vmx.h

@@ -248,12 +248,8 @@ struct vcpu_vmx {
 	 * only loaded into hardware when necessary, e.g. SYSCALL #UDs outside
 	 * of 64-bit mode or if EFER.SCE=1, thus the SYSCALL MSRs don't need to
 	 * be loaded into hardware if those conditions aren't met.
-	 * nr_active_uret_msrs tracks the number of MSRs that need to be loaded
-	 * into hardware when running the guest.  guest_uret_msrs[] is resorted
-	 * whenever the number of "active" uret MSRs is modified.
 	 */
 	struct vmx_uret_msr   guest_uret_msrs[MAX_NR_USER_RETURN_MSRS];
-	int                   nr_active_uret_msrs;
 	bool                  guest_uret_msrs_loaded;
 #ifdef CONFIG_X86_64
 	u64		      msr_host_kernel_gs_base;