fix: Use correct MangoHUD path on 32-bit games (#417)

There was no way previously for MangoHUD to work if it required the
32-bit versions if its libraries due to our replacing of the dynamic
linker's `$LIB`. This PR fixes that and corrects the path to the
libraries located in `$SNAP`.

snap/snapcraft.yaml

@@ -284,10 +284,11 @@ parts:
       - libwayland-dev
       - libxkbcommon-dev:i386
       - libxkbcommon-dev
-    # Fixes the $LIB being escaped for some reason
+    stage-packages:
+      - libxkbcommon0:i386
     override-build: |
         craftctl default
-        sed -i 's/\/usr\/\\\$LIB/\$SNAP\/usr\/lib\/x86_64-linux-gnu/' $CRAFT_PART_INSTALL/usr/bin/mangohud
+        sed -i 's/\/usr\/\\\$LIB/\$SNAP\/usr\/\\\$LIB/' $CRAFT_PART_INSTALL/usr/bin/mangohud
 
   mangohud64:
     after: [meson-deps, mangohud]