pmix: use "''${!outputDev}" instead of $dev

This allows disabling multiple outputs more easily, as the first will
evaluate to $out if a "dev" output is not enabled.

pkgs/development/libraries/pmix/default.nix

@@ -82,19 +82,19 @@ stdenv.mkDerivation (finalAttrs: {
 
     # The path to the pmixcc-wrapper-data.txt is hard coded and
     # points to $out instead of dev. Use wrapper to fix paths.
-    wrapProgram $dev/bin/pmixcc \
-      --set PMIX_INCLUDEDIR $dev/include \
-      --set PMIX_PKGDATADIR $dev/share/pmix
+    wrapProgram "''${!outputDev}"/bin/pmixcc \
+      --set PMIX_INCLUDEDIR "''${!outputDev}"/include \
+      --set PMIX_PKGDATADIR "''${!outputDev}"/share/pmix
   '';
 
   postFixup = ''
     # The build info (parameters to ./configure) are hardcoded
     # into the library. This clears all references to $dev/include.
-    remove-references-to -t $dev $(readlink -f $out/lib/libpmix.so)
+    remove-references-to -t "''${!outputDev}" $(readlink -f $out/lib/libpmix.so)
 
     # Pin the compiler to the current version in a cross compiler friendly way.
     # Same pattern as for openmpi (see https://github.com/NixOS/nixpkgs/pull/58964#discussion_r275059427).
-    substituteInPlace $dev/share/pmix/pmixcc-wrapper-data.txt \
+    substituteInPlace "''${!outputDev}"/share/pmix/pmixcc-wrapper-data.txt \
       --replace-fail compiler=gcc \
         compiler=${targetPackages.stdenv.cc}/bin/${targetPackages.stdenv.cc.targetPrefix}cc
   '';