winrt: Removed WinRT/Windows Phone/UWP support.

Fixes #10724.

src/thread/windows/SDL_syssem.c

@@ -60,18 +60,11 @@ static SDL_sem_impl_t SDL_sem_impl_active = { 0 };
 // APIs not available on WinPhone 8.1
 // https://www.microsoft.com/en-us/download/details.aspx?id=47328
 
-#if !SDL_WINAPI_FAMILY_PHONE
-#ifdef SDL_PLATFORM_WINRT
-// Functions are guaranteed to be available
-#define pWaitOnAddress       WaitOnAddress
-#define pWakeByAddressSingle WakeByAddressSingle
-#else
 typedef BOOL(WINAPI *pfnWaitOnAddress)(volatile VOID *, PVOID, SIZE_T, DWORD);
 typedef VOID(WINAPI *pfnWakeByAddressSingle)(PVOID);
 
 static pfnWaitOnAddress pWaitOnAddress = NULL;
 static pfnWakeByAddressSingle pWakeByAddressSingle = NULL;
-#endif
 
 typedef struct SDL_semaphore_atom
 {
@@ -196,7 +189,6 @@ static const SDL_sem_impl_t SDL_sem_impl_atom = {
     &SDL_GetSemaphoreValue_atom,
     &SDL_SignalSemaphore_atom,
 };
-#endif // !SDL_WINAPI_FAMILY_PHONE
 
 /**
  * Fallback Semaphore implementation using Kernel Semaphores
@@ -217,12 +209,7 @@ static SDL_Semaphore *SDL_CreateSemaphore_kern(Uint32 initial_value)
     sem = (SDL_sem_kern *)SDL_malloc(sizeof(*sem));
     if (sem) {
         // Create the semaphore, with max value 32K
-// !!! FIXME: CreateSemaphoreEx is available in Vista and later, so if XP support is dropped, we can lose this #ifdef.
-#ifdef SDL_PLATFORM_WINRT
-        sem->id = CreateSemaphoreEx(NULL, initial_value, 32 * 1024, NULL, 0, SEMAPHORE_ALL_ACCESS);
-#else
         sem->id = CreateSemaphore(NULL, initial_value, 32 * 1024, NULL);
-#endif
         sem->count = initial_value;
         if (!sem->id) {
             SDL_SetError("Couldn't create semaphore");
@@ -316,12 +303,7 @@ SDL_Semaphore *SDL_CreateSemaphore(Uint32 initial_value)
         // Default to fallback implementation
         const SDL_sem_impl_t *impl = &SDL_sem_impl_kern;
 
-#if !SDL_WINAPI_FAMILY_PHONE
         if (!SDL_GetHintBoolean(SDL_HINT_WINDOWS_FORCE_SEMAPHORE_KERNEL, false)) {
-#ifdef SDL_PLATFORM_WINRT
-            // Link statically on this platform
-            impl = &SDL_sem_impl_atom;
-#else
             /* We already statically link to features from this Api
              * Set (e.g. WaitForSingleObject). Dynamically loading
              * API Sets is not explicitly documented but according to
@@ -338,9 +320,7 @@ SDL_Semaphore *SDL_CreateSemaphore(Uint32 initial_value)
                     impl = &SDL_sem_impl_atom;
                 }
             }
-#endif
         }
-#endif
 
         // Copy instead of using pointer to save one level of indirection
         SDL_copyp(&SDL_sem_impl_active, impl);