types/ptr: deprecate ptr.To, use Go 1.26 new

Updates #18682

Change-Id: I62f6aa0de2a15ef8c1435032c6aa74a181c25f8f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

wgengine/magicsock/magicsock_test.go

@@ -63,7 +63,6 @@ import (
 	"tailscale.com/types/netlogtype"
 	"tailscale.com/types/netmap"
 	"tailscale.com/types/nettype"
-	"tailscale.com/types/ptr"
 	"tailscale.com/types/views"
 	"tailscale.com/util/cibuild"
 	"tailscale.com/util/clientmetric"
@@ -2309,7 +2308,7 @@ func TestIsWireGuardOnlyPeerWithMasquerade(t *testing.T) {
 				IsWireGuardOnly:               true,
 				Addresses:                     []netip.Prefix{wgaip},
 				AllowedIPs:                    []netip.Prefix{wgaip},
-				SelfNodeV4MasqAddrForThisPeer: ptr.To(masqip.Addr()),
+				SelfNodeV4MasqAddrForThisPeer: new(masqip.Addr()),
 			},
 		}),
 	}

wgengine/wgcfg/wgcfg_clone.go

@@ -10,7 +10,6 @@ import (
 
 	"tailscale.com/types/key"
 	"tailscale.com/types/logid"
-	"tailscale.com/types/ptr"
 )
 
 // Clone makes a deep copy of Config.
@@ -56,10 +55,10 @@ func (src *Peer) Clone() *Peer {
 	*dst = *src
 	dst.AllowedIPs = append(src.AllowedIPs[:0:0], src.AllowedIPs...)
 	if dst.V4MasqAddr != nil {
-		dst.V4MasqAddr = ptr.To(*src.V4MasqAddr)
+		dst.V4MasqAddr = new(*src.V4MasqAddr)
 	}
 	if dst.V6MasqAddr != nil {
-		dst.V6MasqAddr = ptr.To(*src.V6MasqAddr)
+		dst.V6MasqAddr = new(*src.V6MasqAddr)
 	}
 	return dst
 }