libvpx

vp9_spatial_svc_encoder.sh: Disable existing tests, add a test that works.

- vp9_spatial_svc_encoder.c no longer supports the -m parameter that
  has been used in the example test. Tests using -m have been disabled.
- Added a basic test that appears to work as of commit
  3249f26ff85e2bfe148167ce80df53643a89a2d2.
- Minor style clean up.

Change-Id: Ic1402fcbbe28e33982c5ea12d1e3349f4069a5bf