rdma-core: Fix pkg-config files

pkgs/os-specific/linux/rdma-core/default.nix

@@ -23,6 +23,12 @@ stdenv.mkDerivation rec {
     "-DCMAKE_INSTALL_SHAREDSTATEDIR=/var/lib"
   ];
 
+  patches = [
+    # this has been fixed in master. As soon as it gets into a release, this
+    # patch won't apply anymore and can be removed.
+    ./pkg-config-template.patch
+  ];
+
   postPatch = ''
     substituteInPlace srp_daemon/srp_daemon.sh.in \
       --replace /bin/rm rm

pkgs/os-specific/linux/rdma-core/pkg-config-template.patch

@@ -0,0 +1,14 @@
+diff -ru source/buildlib/template.pc.in source-fixed/buildlib/template.pc.in
+--- source/buildlib/template.pc.in	1970-01-01 01:00:01.000000000 +0100
++++ source-fixed/buildlib/template.pc.in	2022-03-30 22:29:12.988625941 +0200
+@@ -1,7 +1,6 @@
+-prefix=@CMAKE_INSTALL_PREFIX@
+-exec_prefix=${prefix}
+-libdir=${prefix}/@CMAKE_INSTALL_LIBDIR@
+-includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@
++exec_prefix=@CMAKE_INSTALL_PREFIX@
++libdir=@CMAKE_INSTALL_LIBDIR@
++includedir=@CMAKE_INSTALL_INCLUDEDIR@
+ 
+ Name: lib@PC_LIB_NAME@
+ Description: RDMA Core Userspace Library