st/mesa: implement GL_ATI_fragment_shader

v2: fix arithmetic for special opcodes,
 fix fog state, cleanup
v3: simplify handling of special opcodes,
 fix rebinding with different textargets or fog equation,
 lots of formatting fixes
v4: adapt to the compile early, fix later architecture,
 formatting fixes

Signed-off-by: Miklós Máté <mtmkls@gmail.com>
Signed-off-by: Marek Olšák <marek.olsak@amd.com>
10 files changed