speex: disable neon for arm64

The neon instructions in libspeex/resample_neon.h fail to compile
on arm64:
Error: unknown mnemonic `vld1.16' -- `vld1.16 {d16},[x3]!'
Error: unknown mnemonic `vld1.16' -- `vld1.16 {d20},[x6]!'
Error: unknown mnemonic `vmull.s16' -- `vmull.s16 q0,d16,d20'
Error: unknown mnemonic `vld1.16' -- `vld1.16 {d16,d17,d18,d19},[x3]!'
Error: unknown mnemonic `vld1.16' -- `vld1.16 {d20,d21,d22,d23},[x6]!'
...

Disable neon on arm64 for now.

Change-Id: Ifa2a99696241f53b2d6b25c2cb4330b819699a6f
diff --git a/Android.mk b/Android.mk
index d33e184..b63528e 100644
--- a/Android.mk
+++ b/Android.mk
@@ -51,8 +51,12 @@
 LOCAL_CFLAGS += -DEXPORT= -DFIXED_POINT -DRESAMPLE_FORCE_FULL_SINC_TABLE
 LOCAL_CFLAGS += -O3 -fstrict-aliasing -fprefetch-loop-arrays
 
+ifeq ($(TARGET_ARCH),arm64)
+$(warning TODOArm64: enable neon in libspeex)
+endif
+
 ifeq ($(ARCH_ARM_HAVE_NEON),true)
-LOCAL_CFLAGS += -D_USE_NEON
+LOCAL_CFLAGS_arm += -D_USE_NEON
 endif
 
 LOCAL_C_INCLUDES += \