Bump third_party/libwebsockets/repo from c57c239 to ef4a85d

Bumps [third_party/libwebsockets/repo](https://github.com/warmcat/libwebsockets) from `c57c239` to `ef4a85d`.
- [Commits](warmcat/libwebsockets@c57c239...ef4a85d)

---
updated-dependencies:
- dependency-name: third_party/libwebsockets/repo
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

third_party/libwebsockets/repo

@@ -0,0 +1 @@
+ef4a85d0e14270e83ce74213a0b4bb53e29a07be