i965: Change brw_shader to gl_shader in brw_link_shader().
i965: Change brw_shader to gl_shader in brw_link_shader().

Nothing actually wanted brw_shader fields - we just had to type
shader->base all over the place for no reason.

Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Reviewed-by: Jason Ekstrand <b186559eaedf698788888c8a2559b4efb4db10d6@intel.com>
Reviewed-by: Ian Romanick <2b237cafb16dc45038e85df6c85e74e6d899eba9@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler