r300g: kill off r300_fragment_shader::shadow_samplers and friends

src/gallium/drivers/r300/r300_fs.c

 
     r300_tgsi_to_rc(&ttr, tokens);
 
-    shader->shadow_samplers = compiler.Base.Program.ShadowSamplers;
-
     /**
      * Transform the program to support WPOS.
      *

src/gallium/drivers/r300/r300_fs.h

      * compilation failure. */
     boolean dummy;
 
-    /* Bits 0-15: TRUE if it's a shadow sampler, FALSE otherwise. */
-    unsigned shadow_samplers;
-
     /* Numbers of constants for each type. */
     unsigned externals_count;
     unsigned immediates_count;
     /* Parent class */
     struct pipe_shader_state state;
 
-    /* Bits 0-15: TRUE if it's a shadow sampler, FALSE otherwise.
-     * Initialized from the first compiled FS. */
-    unsigned shadow_samplers;
-
     /* Currently-bound fragment shader. */
     struct r300_fragment_shader_code* shader;