SurfaceFlingerProperties: Use proper prop scope

* System scope is deperecated,
  Public scope should be used instead

Test: m
Change-Id: I758f41c4c6ec31f6781ebe87f8317063763f7134
diff --git a/services/surfaceflinger/sysprop/SurfaceFlingerProperties.sysprop b/services/surfaceflinger/sysprop/SurfaceFlingerProperties.sysprop
index 7b1f0fb..7666f7f 100644
--- a/services/surfaceflinger/sysprop/SurfaceFlingerProperties.sysprop
+++ b/services/surfaceflinger/sysprop/SurfaceFlingerProperties.sysprop
@@ -72,7 +72,7 @@
 prop {
     api_name: "max_graphics_width"
     type: Integer
-    scope: System
+    scope: Public
     access: Readonly
     prop_name: "ro.surface_flinger.max_graphics_width"
 }
@@ -82,7 +82,7 @@
 prop {
     api_name: "max_graphics_height"
     type: Integer
-    scope: System
+    scope: Public
     access: Readonly
     prop_name: "ro.surface_flinger.max_graphics_height"
 }