error: SDL's allocators now call SDL_OutOfMemory on error.

This means the allocator's caller doesn't need to use SDL_OutOfMemory directly
if the allocation fails.

This applies to the usual allocators: SDL_malloc, SDL_calloc, SDL_realloc
(all of these regardless of if the app supplied a custom allocator or we're
using system malloc() or an internal copy of dlmalloc under the hood),
SDL_aligned_alloc, SDL_small_alloc, SDL_strdup, SDL_asprintf, SDL_wcsdup...
probably others. If it returns something you can pass to SDL_free, it should
work.

The caller might still need to use SDL_OutOfMemory if something that wasn't
SDL allocated the memory: operator new in C++ code, Objective-C's alloc
message, win32 GlobalAlloc, etc.

Fixes #8642.

src/SDL_hashtable.c

@@ -54,14 +54,12 @@ SDL_HashTable *SDL_CreateHashTable(void *data, const Uint32 num_buckets, const S
 
     table = (SDL_HashTable *) SDL_calloc(1, sizeof (SDL_HashTable));
     if (!table) {
-        SDL_OutOfMemory();
         return NULL;
     }
 
     table->table = (SDL_HashItem **) SDL_calloc(num_buckets, sizeof (SDL_HashItem *));
     if (!table->table) {
         SDL_free(table);
-        SDL_OutOfMemory();
         return NULL;
     }
 
@@ -92,7 +90,6 @@ SDL_bool SDL_InsertIntoHashTable(SDL_HashTable *table, const void *key, const vo
     // !!! FIXME: grow and rehash table if it gets too saturated.
     item = (SDL_HashItem *) SDL_malloc(sizeof (SDL_HashItem));
     if (!item) {
-        SDL_OutOfMemory();
         return SDL_FALSE;
     }