Add optimization of Skia S32A_Opaque blitter

Adds optimization of Skia S32A_Opaque_BlitRow32 blitter using ARM NEON
instruction set. Special cases for when alpha is zero or opaque.
Improves performance platform wide.

Change-Id: I0ffeb23b128e61cfe581ad121f227631d2918686
Signed-off-by: Henrik Smiding <henrik.smiding@stericsson.com>
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>

Conflicts:
	Android.mk