Remove unnecessary code.

After the commit "Link against NEON version of libclcore.bc when
possible", we don't need to do the selection in libRS.so.

Change-Id: I4cdaf184021f07d055b8f2c38b4b4faffef81706
diff --git a/Android.mk b/Android.mk
index 867cc84..08fa6dc 100644
--- a/Android.mk
+++ b/Android.mk
@@ -2,9 +2,6 @@
 LOCAL_PATH:=$(call my-dir)
 
 rs_base_CFLAGS := -Werror -Wall -Wno-unused-parameter -Wno-unused-variable
-ifeq ($(ARCH_ARM_HAVE_NEON), true)
-  rs_base_CFLAGS += -DARCH_ARM_HAVE_NEON
-endif
 ifeq ($(TARGET_BUILD_PDK), true)
   rs_base_CFLAGS += -D__RS_PDK__
 endif