dnsmasq: 2.92 -> 2.92rel2

Fixes CVE-2026-2291
Fixes CVE-2026-4890
Fixes CVE-2026-4891
Fixes CVE-2026-4892
Fixes CVE-2026-4893
Fixes CVE-2026-5172

https://kb.cert.org/vuls/id/471747

Changelog:
```
version 2.92rel2
        2.92 point release incorporating fixes for
	CVE-2026-2291
	CVE-2026-4890
	CVE-2026-4891
	CVE-2026-4892
	CVE-2026-4893
	CVE-2026-5172
```

pkgs/by-name/dn/dnsmasq/package.nix

@@ -30,11 +30,11 @@ let
 in
 stdenv.mkDerivation (finalAttrs: {
   pname = "dnsmasq";
-  version = "2.92";
+  version = "2.92rel2";
 
   src = fetchurl {
     url = "https://www.thekelleys.org.uk/dnsmasq/dnsmasq-${finalAttrs.version}.tar.xz";
-    hash = "sha256-S/UMLBAY+fvCYDffUbkOzqDLc9RhYoRnY7kt8NbDpFg=";
+    hash = "sha256-Q9crjBKb3zPRe6/tyYgj9j5GtQBRKAZr8NKkcqMs4Go=";
   };
 
   patches = [