Cherry-pick RELEASES.md from release-branch/0.17.12.

Pick up the changelog entry for 0.17.12.

RELEASES.md

@@ -0,0 +1,15 @@
+Version 0.17.12 (2025-03-05)
+============================
+Bug fix: https://github.com/briansmith/ring/pull/2447 for denial of service (DoS).
+
+Fixes a panic in `ring::aead::quic::HeaderProtectionKey::new_mask()` when
+integer overflow checking is enabled. Integer overflow checking is not enabled
+in release mode by default, but `RUSTFLAGS="-C overflow-checks"` or
+`overflow-checks = true` in the Cargo.toml profile can override this.
+
+Fixes a panic in when using `ring::aead::{AES_128_GCM, AES_256_GCM}` when
+integer overflow checking is enabled, when  encrypting/decrypting approximately
+68,719,476,700 bytes (about 64 gigabytes) of data in a single chunk. Integer
+overflow checking is not enabled in release mode by default, but
+`RUSTFLAGS="-C overflow-checks"` or `overflow-checks = true` in the Cargo.toml
+profile can override this.