Revert "Match swrast modes more loosely."
Revert "Match swrast modes more loosely."

This reverts commit f3728a16c9c6a02fc1f44b8069b0060e2358f22e.

It broke glxgears on radeonsi. The window was just black.

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler