gnu: jbig2dec: Remove graft for 0.15.

* gnu/packages/image.scm (jbig2dec): Update to 0.15.
[source]: Reindent.
(jbig2dec-0.15): Remove variable.

gnu/packages/image.scm

@@ -485,17 +485,16 @@ arithmetic ops.")
 (define-public jbig2dec
   (package
     (name "jbig2dec")
-    (version "0.14")
-    (replacement jbig2dec-0.15)
-    (source
-      (origin
-        (method url-fetch)
-        (uri
-         (string-append "https://github.com/ArtifexSoftware/ghostpdl-downloads/"
-                        "releases/download/gs922/" name "-" version ".tar.gz"))
-        (sha256
-          (base32 "0k01hp0q4275fj4rbr1gy64svfraw5w7wvwl08yjhvsnpb1rid11"))
-        (patches (search-patches "jbig2dec-ignore-testtest.patch"))))
+    (version "0.15")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://github.com/ArtifexSoftware"
+                                  "/ghostpdl-downloads/releases/download"
+                                  "/gs924/" name "-" version ".tar.gz"))
+              (sha256
+               (base32
+                "0m1qwpbjbirgw2fqznbajdhdhh35d6xa2csr64lpjz735pvimykb"))
+              (patches (search-patches "jbig2dec-ignore-testtest.patch"))))
     (build-system gnu-build-system)
     (arguments '(#:configure-flags '("--disable-static")))
     (synopsis "Decoder of the JBIG2 image compression format")
@@ -512,21 +511,6 @@ work.")
     (home-page "https://jbig2dec.com")
     (license license:gpl2+)))
 
-;; This is a bugfix release from an ongoing Ghostscript security audit.
-;; It was released alongside Ghostscript 9.24.
-(define-public jbig2dec-0.15
-  (package
-    (inherit jbig2dec)
-    (version "0.15")
-    (source (origin
-              (inherit (package-source jbig2dec))
-              (uri (string-append "https://github.com/ArtifexSoftware"
-                                  "/ghostpdl-downloads/releases/download/gs924/"
-                                  "jbig2dec-" version ".tar.gz"))
-              (sha256
-               (base32
-                "0m1qwpbjbirgw2fqznbajdhdhh35d6xa2csr64lpjz735pvimykb"))))))
-
 (define-public openjpeg
   (package
     (name "openjpeg")