Remove ANGLE from base_system.mk

Removing GoogleANGLE only removed the Google-signed version of ANGLE,
but the AOSP version still remained. This CL removes the AOSP build of
ANGLE also, so there is no ANGLE on the device at all.

Bug: 158956138
Test: adb shell pm list packages | grep -i angle
Change-Id: If9a42bc6436c752d2b1a16565d99ca2a5ec60d66
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index 7c5c809..f0b52c0 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -27,7 +27,6 @@
     android.test.base \
     android.test.mock \
     android.test.runner \
-    ANGLE \
     apexd \
     appops \
     app_process \