goldfish-opengl: stop checking DWITH_GLES2

It's always enabled anyways.

BUG=202552093
TEST=compile

Change-Id: I4506dd9a6c97c3bfbc65d9f5c946a4f587ed40cb
diff --git a/Android.mk b/Android.mk
index 3444354..5ac775e 100644
--- a/Android.mk
+++ b/Android.mk
@@ -29,10 +29,9 @@
 # See the definition of emugl-begin-module in common.mk
 EMUGL_COMMON_INCLUDES := $(GOLDFISH_OPENGL_PATH)/host/include/libOpenglRender $(GOLDFISH_OPENGL_PATH)/system/include
 
-# common cflags used by several modules
 # This is always set to a module's LOCAL_CFLAGS
 # See the definition of emugl-begin-module in common.mk
-EMUGL_COMMON_CFLAGS := -DWITH_GLES2
+EMUGL_COMMON_CFLAGS :=
 
 # Whether or not to build the Vulkan library.
 GFXSTREAM := false