cell: perform triangle cull a little earlier
cell: perform triangle cull a little earlier

In spu_tri.c:setup_sort_vertices() triangles are culled after the
vertices are sorted.  This patch moves the check a little earlier
and performs the actual check a little faster through intrinsics and
a little trickery.

Reduced code size and less work is done before a triangle is deemed
OK to skip.

mcanthony/glsl-optimizer,tokyovigilante/glsl-optimizer,zeux/glsl-optimizer,wolf96/glsl-optimizer,zz85/glsl-optimizer,adobe/glsl2agal,bkaradzic/glsl-optimizer,benaadams/glsl-optimizer,KTXSoftware/glsl2agal,zz85/glsl-optimizer,KTXSoftware/glsl2agal,tokyovigilante/glsl-optimizer,jbarczak/glsl-optimizer,mapbox/glsl-optimizer,dellis1972/glsl-optimizer,zz85/glsl-optimizer,jbarczak/glsl-optimizer,tokyovigilante/glsl-optimizer,djreep81/glsl-optimizer,zeux/glsl-optimizer,bkaradzic/glsl-optimizer,KTXSoftware/glsl2agal,zeux/glsl-optimizer,djreep81/glsl-optimizer,wolf96/glsl-optimizer,bkaradzic/glsl-optimizer,mcanthony/glsl-optimizer,zz85/glsl-optimizer,dellis1972/glsl-optimizer,wolf96/glsl-optimizer,adobe/glsl2agal,benaadams/glsl-optimizer,metora/MesaGLSLCompiler,djreep81/glsl-optimizer,bkaradzic/glsl-optimizer,benaadams/glsl-optimizer,dellis1972/glsl-optimizer,djreep81/glsl-optimizer,tokyovigilante/glsl-optimizer,benaadams/glsl-optimizer,KTXSoftware/glsl2agal,bkaradzic/glsl-optimizer,mcanthony/glsl-optimizer,zz85/glsl-optimizer,jbarczak/glsl-optimizer,zeux/glsl-optimizer,zz85/glsl-optimizer,benaadams/glsl-optimizer,zeux/glsl-optimizer,wolf96/glsl-optimizer,mapbox/glsl-optimizer,metora/MesaGLSLCompiler,adobe/glsl2agal,wolf96/glsl-optimizer,jbarczak/glsl-optimizer,benaadams/glsl-optimizer,KTXSoftware/glsl2agal,metora/MesaGLSLCompiler,dellis1972/glsl-optimizer,jbarczak/glsl-optimizer,adobe/glsl2agal,dellis1972/glsl-optimizer,mcanthony/glsl-optimizer,mapbox/glsl-optimizer,tokyovigilante/glsl-optimizer,mcanthony/glsl-optimizer,mapbox/glsl-optimizer,adobe/glsl2agal,djreep81/glsl-optimizer,mapbox/glsl-optimizer