gnu: mupen64plus-video-arachnoid: Don't use unstable tarball.

* gnu/packages/emulators.scm (mupen64plus-video-arachnoid)[source]: Use GIT-FETCH and
GIT-FILE-NAME.

gnu/packages/emulators.scm

@@ -689,13 +689,13 @@ Z64 RSP processor plugin.")
     (version "2.0.0")
     (source
      (origin
-       (method url-fetch)
-       (uri (string-append
-             "https://github.com/mupen64plus/mupen64plus-video-arachnoid/archive/"
-             version ".tar.gz"))
-       (file-name (string-append name "-" version ".tar.gz"))
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/mupen64plus/mupen64plus-video-arachnoid.git")
+             (commit version)))
+       (file-name (git-file-name name version))
        (sha256
-        (base32 "0jjwf144rihznm4lnqbhgigxw664v3v32wy94adaa6imk8z6gslh"))))
+        (base32 "1v9fqwpb6pawr8z5cm2ki7bqkks4iyr5c4jy4v5khj6h8zcv55gc"))))
     (build-system gnu-build-system)
     (native-inputs
      `(("pkg-config" ,pkg-config)