Lots of assorted changes for new GLSL compiler backend.

New datatypes, constants, variables.
diff --git a/src/mesa/main/get_gen.py b/src/mesa/main/get_gen.py
index 0f2ca00..5a9ca07 100644
--- a/src/mesa/main/get_gen.py
+++ b/src/mesa/main/get_gen.py
@@ -989,7 +989,7 @@
 	  ["ctx->Const.VertexProgram.MaxUniformComponents"], "",
 	  ["ARB_vertex_shader"] ),
 	( "GL_MAX_VARYING_FLOATS_ARB", GLint,
-	  ["ctx->Const.MaxVaryingFloats"], "", ["ARB_vertex_shader"] ),
+	  ["ctx->Const.MaxVarying * 4"], "", ["ARB_vertex_shader"] ),
 	( "GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS_ARB", GLint,
 	  ["ctx->Const.MaxVertexTextureImageUnits"], "", ["ARB_vertex_shader"] ),
 	( "GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS_ARB", GLint,