codec2: fix paths in pkg-config file

pkgs/by-name/co/codec2/fix-pkg-config.patch

···
+diff --git a/codec2.pc.in b/codec2.pc.in
+index ecca704..94fca12 100644
+--- a/codec2.pc.in
++++ b/codec2.pc.in
+@@ -1,6 +1,5 @@
+-prefix=@CMAKE_INSTALL_PREFIX@
+-libdir=@CMAKE_INSTALL_PREFIX@/@CMAKE_INSTALL_LIBDIR@
+-includedir=@CMAKE_INSTALL_PREFIX@/@CMAKE_INSTALL_INCLUDEDIR@/codec2
++libdir=@CMAKE_INSTALL_LIBDIR@
++includedir=@CMAKE_INSTALL_INCLUDEDIR@/codec2
+ 
+ Name: codec2
+ Description: A speech codec for 2400 bit/s and below

pkgs/by-name/co/codec2/package.nix

···
     hash = "sha256-69Mp4o3MgV98Fqfai4txv5jQw2WpoPuoWcwHsNAFPQM=";
   };
 
+  patches = [
+    # Fix nix-store path dupliucations
+    ./fix-pkg-config.patch
+  ];
+
   nativeBuildInputs = [
     cmake
     buildPackages.stdenv.cc # needs to build a C program to run at build time