Revert "gnu: vlc: Update to 2.2.0"

This reverts commit ad036bda89.

This version has always failed to build according to
<http://hydra.gnu.org/job/gnu/master/vlc-2.2.0.x86_64-linux/all>.

gnu/packages/video.scm

@@ -357,7 +357,7 @@ audio/video codec library.")
 (define-public vlc
   (package
     (name "vlc")
-    (version "2.2.0")
+    (version "2.1.5")
     (source (origin
              (method url-fetch)
              (uri (string-append
@@ -365,7 +365,7 @@ audio/video codec library.")
                    version "/vlc-" version ".tar.xz"))
              (sha256
               (base32
-               "05smn9hqdp7iscc1dj4cxp1mrlad7b50lhlnlqisfzf493i2f2jy"))))
+               "0whzbn7ahn5maarcwl1yhk9lq10b0q0y9w5pjl9kh3frdjmncrbg"))))
     (build-system gnu-build-system)
     (native-inputs
      `(("git" ,git) ; needed for a test