Never specify /O1

Leaving it as /O2 might improve performance.
Stops this from being spammed:
cl : command line  warning D9025: overriding '/O2' with '/O1' [D:\a\xenia-canary\xenia-canary\build\glslang-spirv.vcxproj]

/Os is implied by /O1;
https://learn.microsoft.com/en-us/cpp/build/reference/o1-o2-minimize-size-maximize-speed?view=msvc-170

src/xenia/ui/premake5.lua

@@ -14,11 +14,10 @@ project("xenia-ui")
   local_platform_files()
   removefiles({"*_demo.cc"})
   removefiles({"windowed_app_main_*.cc"})
-  filter({"configurations:Release", "platforms:Windows"})
-    buildoptions({
-      "/Os",
-      "/O1"
-    })
+--  filter({"configurations:Release", "platforms:Windows"})
+--    buildoptions({
+--      "/O1",
+--    })
   filter("platforms:Android-*")
     -- Exports JNI functions.
     wholelib("On")