Fix NEON and SSE handling

The existing version handled SSE case more-or-less correctly but
ARM case was completely broken: it actually never used DSP/NEON/etc.

Fix the build and use proper logic to handle devices with and without
NEON support.

Change-Id: I74fe48f0b5df70c921c3dc7993e4d72e30e26cf0
1 file changed