Migrate libEGL to ndk_library.

Test: make checkbuild
Bug: http://b/30465923
Change-Id: I154a95c6fde9c34d770b6fe65bfd71ac51e05574
diff --git a/Android.bp b/Android.bp
index f5620f8..d402651 100644
--- a/Android.bp
+++ b/Android.bp
@@ -8,6 +8,6 @@
 subdirs = [
     "cmds/*",
     "libs/*",
-    "opengl/*",
+    "opengl",
     "services/*",
 ]