Added SDL_DelayPrecise()

SDL_DelayNS() now passes through to the high precision OS delay function, and SDL_DelayPrecise() tries to busy wait to get as close as possible to the desired wait time.

Fixes https://github.com/libsdl-org/SDL/issues/11141

src/dynapi/SDL_dynapi.sym

@@ -1177,6 +1177,7 @@ SDL3_0.0.0 {
     SDL_wcsstr;
     SDL_wcstol;
     SDL_StepBackUTF8;
+    SDL_DelayPrecise;
     # extra symbols go here (don't modify this line)
   local: *;
 };