Add shader for Repeat_SI8_opaque_D32_filter_DX.

Adds a NEON optimized shader for SI8_opaque_D32_filter_DX when
running with repeat tile mode.
Improves performance of browser.

Change-Id: Ic5cc63b3df86eb7e8ea0bbb3b7bddfc73db20025
Signed-off-by: Henrik Smiding <henrik.smiding@stericsson.com>
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>