Neon optimized implementation of S16_opaque_D32_nofilter_DX

This patch does the following:
* Neon ASM blitter from RGB565 to ABGR8888 without blend.
* Special case for no scaling but the scaling case is almost as fast.

 Copyright (C) ST-Ericsson SA 2010

Change-Id: I56b789e8ad36072625d498d0da27658831cfff6d