Update resource name for wallpapers

Commit platform/packages/apps/WallpaperPicker2@af6d4ba has changed
the resource name back to 'partner_wallpapers' to support legacy
namings. Hence update the name accordingly.

Issue: FP3-A13#109
Change-Id: I7c5ba6afc3b37b081079592e00bac843993f3d13
diff --git a/themes/res/values/arrays.xml b/themes/res/values/arrays.xml
index 94116b4..3be50cc 100644
--- a/themes/res/values/arrays.xml
+++ b/themes/res/values/arrays.xml
@@ -16,7 +16,7 @@
  -->
 
 <resources>
-    <string-array name="wallpapers" translatable="false">
+    <string-array name="partner_wallpapers" translatable="false">
         <item>wallpaper_01</item>
         <item>wallpaper_02</item>
         <item>wallpaper_03</item>