intel/compiler: Silence unused parameter warnings in generate_foo methods

intel/compiler: Silence unused parameter warnings in generate_foo methods

Since all of the fs_generator::generate_foo methods take a fs_inst * as
the first parameter, just remove the name to quiet the compiler.

src/intel/compiler/brw_fs_generator.cpp: In member function ‘void fs_generator::generate_barrier(fs_inst*, brw_reg)’:
src/intel/compiler/brw_fs_generator.cpp:743:41: warning: unused parameter ‘inst’ [-Wunused-parameter]
 fs_generator::generate_barrier(fs_inst *inst, struct brw_reg src)
                                         ^~~~
src/intel/compiler/brw_fs_generator.cpp: In member function ‘void fs_generator::generate_discard_jump(fs_inst*)’:
src/intel/compiler/brw_fs_generator.cpp:1326:46: warning: unused parameter ‘inst’ [-Wunused-parameter]
 fs_generator::generate_discard_jump(fs_inst *inst)
                                              ^~~~
src/intel/compiler/brw_fs_generator.cpp: In member function ‘void fs_generator::generate_pack_half_2x16_split(fs_inst*, brw_reg, brw_reg, brw_reg)’:
src/intel/compiler/brw_fs_generator.cpp:1675:54: warning: unused parameter ‘inst’ [-Wunused-parameter]
 fs_generator::generate_pack_half_2x16_split(fs_inst *inst,
                                                      ^~~~
src/intel/compiler/brw_fs_generator.cpp: In member function ‘void fs_generator::generate_shader_time_add(fs_inst*, brw_reg, brw_reg, brw_reg)’:
src/intel/compiler/brw_fs_generator.cpp:1743:49: warning: unused parameter ‘inst’ [-Wunused-parameter]
 fs_generator::generate_shader_time_add(fs_inst *inst,
                                                 ^~~~
src/intel/compiler/brw_vec4_generator.cpp: In function ‘void generate_set_simd4x2_header_gen9(brw_codegen*, brw::vec4_instruction*, brw_reg)’:
src/intel/compiler/brw_vec4_generator.cpp:1412:52: warning: unused parameter ‘inst’ [-Wunused-parameter]
                                  vec4_instruction *inst,
                                                    ^~~~
src/intel/compiler/brw_vec4_generator.cpp: In function ‘void generate_mov_indirect(brw_codegen*, brw::vec4_instruction*, brw_reg, brw_reg, brw_reg, brw_reg)’:
src/intel/compiler/brw_vec4_generator.cpp:1430:41: warning: unused parameter ‘inst’ [-Wunused-parameter]
                       vec4_instruction *inst,
                                         ^~~~
src/intel/compiler/brw_vec4_generator.cpp:1432:63: warning: unused parameter ‘length’ [-Wunused-parameter]
                       struct brw_reg indirect, struct brw_reg length)
                                                               ^~~~~~
Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>