[spirv] nuke spirv-opt (#3877)

lots of AGILEism in spirv-opt
theres BETTER alternatives like https://github.com/renderbag/re-spirv (im not gonna bother for now, it probably has shitty build system)
it sucks

the IR already resolves most of the shader code to just constant load/stores
Spirv-opt passes do not seem to make such a big difference
only introduce extra latency
like for example cbuf pass in IR already removes a lot of code, that spirv_opt would otherwise miss due to the fact it doesn't have cbuf information

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Co-authored-by: crueter <crueter@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3877
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: crueter <crueter@eden-emu.dev>

src/common/settings.h

@@ -388,10 +388,6 @@ struct Values {
                                                   true,
                                                   true};
 
-    SwitchableSetting<SpirvOptimizeMode, true> optimize_spirv_output{linkage,
-                                                                     SpirvOptimizeMode::Never,
-                                                                     "optimize_spirv_output",
-                                                                     Category::Renderer};
     SwitchableSetting<bool> use_asynchronous_gpu_emulation{
                                                            linkage, true, "use_asynchronous_gpu_emulation", Category::Renderer};
     // *nix platforms may have issues with the borderless windowed fullscreen mode.