Fix arm64 build

ARCH_ARM_HAVE_NEON only applies to ARMv7 targets, since ARMv8 requires
NEON support.  It may be set anyway on some targets but this shouldn't
be relied on.

Also fix DEFAULT_ARCH not getting set, which currently works anyway but
mostly by accident (ihevcd_init_function_ptr() falls back on the case we
happen to want).

Change-Id: Ided35523f83fdffca313e2bcb71470cdf780fa55
Signed-off-by: Greg Hackmann <ghackmann@google.com>
1 file changed