Remove FlagManager's dependence on librenderengine

libsurfaceflinger_common_defaults previously depended on
librenderengine, but only for a #define in a header file. This prevents
librenderengine from using the FlagManager.

Add a new library for renderengine includes, so FlagManager can access
the define without depending on the entire library.

Bug: 305445199
Bug: 255921628
Test: make
Change-Id: Ibee8581cfc0ac8c4817725bbf1fb12efc744c4c1
diff --git a/services/surfaceflinger/common/Android.bp b/services/surfaceflinger/common/Android.bp
index 5ef22b5..e125bbe 100644
--- a/services/surfaceflinger/common/Android.bp
+++ b/services/surfaceflinger/common/Android.bp
@@ -18,7 +18,7 @@
         "server_configurable_flags",
     ],
     static_libs: [
-        "librenderengine",
+        "librenderengine_includes",
     ],
     srcs: [
         "FlagManager.cpp",