niv musl-wasi: update ec4566be -> 4db5398e (#4220)

## Changelog for musl-wasi:
Branch: main
Commits: [WebAssembly/wasi-libc@ec4566be...4db5398e](WebAssembly/wasi-libc@ec4566b...4db5398)

* [`ce2f157d`](WebAssembly/wasi-libc@ce2f157) Update thread id validation returned by `__wasi_thread_spawn` ([WebAssembly/wasi-libc⁠#435](https://togithub.com/WebAssembly/wasi-libc/issues/435))
* [`7b4705f1`](WebAssembly/wasi-libc@7b4705f) Fix typo in signal.c error messages ([WebAssembly/wasi-libc⁠#437](https://togithub.com/WebAssembly/wasi-libc/issues/437))
* [`d4dae896`](WebAssembly/wasi-libc@d4dae89) add shared library support ([WebAssembly/wasi-libc⁠#429](https://togithub.com/WebAssembly/wasi-libc/issues/429))
* [`6248a00c`](WebAssembly/wasi-libc@6248a00) Adjust Makefile for LLVM trunk (18) as of 2023-10-03 ([WebAssembly/wasi-libc⁠#438](https://togithub.com/WebAssembly/wasi-libc/issues/438))
* [`4db5398e`](WebAssembly/wasi-libc@4db5398) remove `-nostdlib` from libc.so link command ([WebAssembly/wasi-libc⁠#440](https://togithub.com/WebAssembly/wasi-libc/issues/440))

nix/sources.json

@@ -102,10 +102,10 @@
         "homepage": "https://wasi.dev",
         "owner": "WebAssembly",
         "repo": "wasi-libc",
-        "rev": "ec4566beae84e54952637f0bf61bee4b4cacc087",
-        "sha256": "0f739yhi5phs2g0p0bl2nx87qmcc4amq2c2nykdycr1lglvqq5yy",
+        "rev": "4db5398e65c7dd343315db7e13f3dcae056466ba",
+        "sha256": "1nznll05xqihh07pvvyrrxm7n56qxcjrqcdy74fgj8dhyim538nz",
         "type": "tarball",
-        "url": "https://github.com/WebAssembly/wasi-libc/archive/ec4566beae84e54952637f0bf61bee4b4cacc087.tar.gz",
+        "url": "https://github.com/WebAssembly/wasi-libc/archive/4db5398e65c7dd343315db7e13f3dcae056466ba.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixpkgs": {