[gnome-build-meta] Flatpak Platform/Sdk: Fix GST_PLUGIN_SYSTEM_PATH enviroment variable

[Jordan Petridis <jpetridis src gnome org>]

commit e669996d8c79f64b98cea0695cb06afabb516c92
Author: Jordan Petridis <jpetridis gnome org>
Date:   Thu Sep 27 00:48:29 2018 +0000

    Flatpak Platform/Sdk: Fix GST_PLUGIN_SYSTEM_PATH enviroment variable
    
    GST_PLUGIN_SYSTEM_PATH is currently at /usr/lib/gstreamer-1.0 which
    is an invalid location. It should point to %{libdir}/... instead.
    
    Relevant freedesktop MR:
    https://gitlab.com/freedesktop-sdk/freedesktop-sdk/merge_requests/527
    
    Close #75
    
    
    (cherry picked from commit d5cec36b54dd7b10547527a916fdf0a87efbb81c)

 elements/flatpak/platform.bst | 2 +-
 elements/flatpak/sdk.bst      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/elements/flatpak/platform.bst b/elements/flatpak/platform.bst
index 049f10a..0950c15 100644
--- a/elements/flatpak/platform.bst
+++ b/elements/flatpak/platform.bst
@@ -16,7 +16,7 @@ config:
 
     Environment:
       GI_TYPELIB_PATH: /app/lib/girepository-1.0
-      GST_PLUGIN_SYSTEM_PATH: /app/lib/gstreamer-1.0:/usr/lib/extensions/gstreamer-1.0:/usr/lib/gstreamer-1.0
+      GST_PLUGIN_SYSTEM_PATH: 
/app/lib/gstreamer-1.0:/usr/lib/extensions/gstreamer-1.0:%{libdir}/gstreamer-1.0
       XDG_DATA_DIRS: /app/share:/usr/share:/usr/share/runtime/share:/run/host/share
 
     Extension org.gnome.Platform.Locale:
diff --git a/elements/flatpak/sdk.bst b/elements/flatpak/sdk.bst
index 529e21c..0574529 100644
--- a/elements/flatpak/sdk.bst
+++ b/elements/flatpak/sdk.bst
@@ -16,7 +16,7 @@ config:
 
     Environment:
       GI_TYPELIB_PATH: /app/lib/girepository-1.0
-      GST_PLUGIN_SYSTEM_PATH: /app/lib/gstreamer-1.0:/usr/lib/extensions/gstreamer-1.0:/usr/lib/gstreamer-1.0
+      GST_PLUGIN_SYSTEM_PATH: 
/app/lib/gstreamer-1.0:/usr/lib/extensions/gstreamer-1.0:%{libdir}/gstreamer-1.0
       XDG_DATA_DIRS: /app/share:/usr/share:/usr/share/runtime/share:/run/host/share
 
     Extension org.gnome.Sdk.Debug: