Full range motion search for regular block sizes

Add a full range motion search for regular block sizes. This runs
exhaustive search within the given reference area. This commit further
optimizes the search process by combining 4 points test into one
pipeline, which gives 30% speed-up as compared to run each individual
point at a time.

This full range search serves as a best possible motion search reference.
When replacing the diamond search with full range search, the speed 0
runtime of bus CIF at 2000 kbps goes from 153872ms to 623051ms. The
compression performance compared to speed 0 setting gains 0.585% for
derf set.

Change-Id: Ieef1225216b0b86b4ac4872fa7fb9e18bf2eabb3