mupdf: fix library linking

Previously, libmupdf.so did not have DT_NEEDED references to its
dependencies. Packages which linked against libmupdf would have to also
manually link against its dependencies as well.

pkgs/applications/misc/mupdf/default.nix

@@ -1,5 +1,5 @@
 { stdenv, lib, fetchurl, fetchpatch, pkgconfig
-, freetype, harfbuzz, openjpeg, jbig2dec
+, freetype, harfbuzz, openjpeg, jbig2dec, libjpeg
 , enableX11 ? true, libX11, libXext
 , enableCurl ? true, curl, openssl
 }:
@@ -26,11 +26,17 @@ stdenv.mkDerivation rec {
       url = "http://git.ghostscript.com/?p=mupdf.git;a=blobdiff_plain;f=platform/x11/jstest_main.c;h=f158d9628ed0c0a84e37fe128277679e8334422a;hp=13c3a0a3ba3ff4aae29f6882d23740833c1d842f;hb=06a012a42c9884e3cd653e7826cff1ddec04eb6e;hpb=34e18d127a02146e3415b33c4b67389ce1ddb614";
       sha256 = "163bllvjrbm0gvjb25lv7b6sih4zr4g4lap3h0cbq8dvpjxx0jfc";
     })
+
+    (fetchpatch {
+      name = "mupdf-1.11-shared_libs-1.patch";
+      url = "http://www.linuxfromscratch.org/patches/downloads/mupdf/mupdf-1.11-shared_libs-1.patch";
+      sha256 = "127x8jhyj3i9cn3mxw9mm5barw2yk43rvmghg54bhn4rjalx857j";
+    })
   ];
 
   makeFlags = [ "prefix=$(out)" ];
   nativeBuildInputs = [ pkgconfig ];
-  buildInputs = [ freetype harfbuzz openjpeg jbig2dec ]
+  buildInputs = [ freetype harfbuzz openjpeg jbig2dec libjpeg ]
                 ++ lib.optionals enableX11 [ libX11 libXext ]
                 ++ lib.optionals enableCurl [ curl openssl ];
   outputs = [ "bin" "dev" "out" "man" "doc" ];
@@ -41,13 +47,6 @@ stdenv.mkDerivation rec {
   '';
 
   postInstall = ''
-    for i in $out/lib/*.a; do
-      so="''${i%.a}.so"
-      gcc -shared -o $so.${version} -Wl,--whole-archive $i -Wl,--no-whole-archive
-      ln -s $so.${version} $so
-      rm $i
-    done
-
     mkdir -p "$out/lib/pkgconfig"
     cat >"$out/lib/pkgconfig/mupdf.pc" <<EOF
     prefix=$out