asm : Hook up luma_vps and luma_vss with the encoder.

--HG--
extra : rebase_source : 1615f0b36d50a66021af63c77f30fc8b3cfd5c8c
asm : Hook up chroma_vps and chroma_vss with the encoder.

--HG--
extra : rebase_source : c67ea6403dbedda63255f3e3f7f95cb18edb6660
pixelharness: remove dead primitive test
primitive: remove dead ipfilter_ps
primitive: remove dead ipfilter_sp and ipfilter_ss
primitive: remove two dead funcdefs
primitves: fix a comment
primitives: move luma_addAvg close to other weight/avg functions
slicetype: issue EMMS before returning a thread to the work pool

--HG--
branch : stable
Merge with stable