Merge pull request #126699 from mdevlamynck/fix-transgui-aarch64

transgui: fix transgui build on aarch64

pkgs/applications/networking/p2p/transgui/default.nix

···
   '';
 
   preBuild = ''
+    FPCDIR=${fpc}/lib/fpc/${fpc.version} fpcmake -w
     lazbuild -B transgui.lpr --lazarusdir=${lazarus}/share/lazarus
   '';