Enable 32-bit armv8 NEON for libbcc and bcc

Since ARM neon instructions were only used on armv7-a-neon
architecture variant, the default implementations for these
binaries don't use these advanced SIMD instructions.

Bug: 65568402
Test: lunch aosp_arm64; emulator # on oc-mr1-dev; boot to home screen
Change-Id: If70be7373288387b1c5259c04f80dd266218bc40
diff --git a/Android.bp b/Android.bp
index f59b4df..f322771 100644
--- a/Android.bp
+++ b/Android.bp
@@ -71,7 +71,7 @@
                 "-DFORCE_ARM_CODEGEN",
                 "-DARCH_ARM_HAVE_VFP",
             ],
-            armv7_a_neon: {
+            neon: {
                 cflags: [
                     "-DARCH_ARM_HAVE_VFP_D32",
                     "-DARCH_ARM_HAVE_NEON",