tools: add VS/PS_RANGE registers to driver state map
driver: rename etna_shader to etna_compiler

Prepare for splitting up etna_pipe.
etna_shader should contain the code from etna_pipe.c
dealing with shader state. etna_compiler does the compilation of
the actual shaders.
driver: swap SCISSOR and VIEWPORT dirty bits

Oops, these were the wrong way around, fixed this.