Deprecate SDL_INIT_EVERYTHING from SDL2

Adds SDL_INIT_EVERYTHING to the deprecated symbol list, and renames an internal usage to avoid a warning.

include/SDL3/SDL_oldnames.h

@@ -1325,6 +1325,7 @@
 #define SDL_GetWindowDisplayIndex SDL_GetWindowDisplayIndex_renamed_SDL_GetDisplayForWindow
 #define SDL_GetWindowDisplayMode SDL_GetWindowDisplayMode_renamed_SDL_GetWindowFullscreenMode
 #define SDL_HasWindowSurface SDL_HasWindowSurface_renamed_SDL_WindowHasSurface
+#define SDL_INIT_EVERYTHING SDL_INIT_EVERYTHING_deprecated_list_flags_explicitly
 #define SDL_IsScreenSaverEnabled SDL_IsScreenSaverEnabled_renamed_SDL_ScreenSaverEnabled
 #define SDL_SetWindowDisplayMode SDL_SetWindowDisplayMode_renamed_SDL_SetWindowFullscreenMode
 #define SDL_WINDOW_ALLOW_HIGHDPI SDL_WINDOW_ALLOW_HIGHDPI_renamed_SDL_WINDOW_HIGH_PIXEL_DENSITY

src/SDL.c

@@ -65,7 +65,7 @@
 #include "core/android/SDL_android.h"
 #endif
 
-#define SDL_INIT_EVERYTHING ~0U
+#define SDL_ALL_SUBSYSTEM_FLAGS ~0U
 
 // Initialization/Cleanup routines
 #include "timer/SDL_timer_c.h"
@@ -682,7 +682,7 @@ Uint32 SDL_WasInit(SDL_InitFlags flags)
     }
 
     if (!flags) {
-        flags = SDL_INIT_EVERYTHING;
+        flags = SDL_ALL_SUBSYSTEM_FLAGS;
     }
 
     num_subsystems = SDL_min(num_subsystems, SDL_MostSignificantBitIndex32(flags) + 1);
@@ -707,7 +707,7 @@ void SDL_Quit(void)
 #ifdef SDL_PLATFORM_WINDOWS
     SDL_HelperWindowDestroy();
 #endif
-    SDL_QuitSubSystem(SDL_INIT_EVERYTHING);
+    SDL_QuitSubSystem(SDL_ALL_SUBSYSTEM_FLAGS);
     SDL_CleanupTrays();
 
 #ifdef SDL_USE_LIBDBUS