[gnome-builder] Make libide's install_dir an absolute path.

[Christian Hergert <chergert src gnome org>]

commit 1011cabc519fd7322e2d695c79bfce3e18ff6200
Author: Jamey Sharp <jamey minilop net>
Date:   Mon Jul 30 13:26:28 2018 -0700

    Make libide's install_dir an absolute path.
    
    As far as I know, this change should be a no-op on all systems where
    Builder works today. However, it is necessary for getting the correct
    shared-library path into generated .gir and typelib files when building
    on Nix, so I'm hoping this is an acceptable change for upstream.

 src/libide/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libide/meson.build b/src/libide/meson.build
index e0643eda4..e27e0e43a 100644
--- a/src/libide/meson.build
+++ b/src/libide/meson.build
@@ -229,7 +229,7 @@ libide = shared_library('ide-' + libide_api_version,
   dependencies: libide_deps,
         c_args: libide_args,
        install: true,
-   install_dir: pkglibdir,
+   install_dir: pkglibdir_abs,
  install_rpath: pkglibdir_abs,
 )