glsl_to_tgsi: fixes for native integers and integer booleans
glsl_to_tgsi: fixes for native integers and integer booleans

This fixes all but one of the piglit regressions from enabling native integers
in softpipe.  The change to fix the last regression is still being discussed.

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