ta: minor simplification for talloc_steal

Since commit f6615f00ee, it can't fail anymore.

ta/ta.h

@@ -125,14 +125,12 @@ bool ta_vasprintf_append_buffer(char **str, const char *fmt, va_list ap) TA_PRF(
 #define ta_xnew_array_ptrtype(...)      ta_oom_g(ta_new_array_ptrtype(__VA_ARGS__))
 #define ta_xdup(...)                    ta_oom_g(ta_dup(__VA_ARGS__))
 
-#define ta_xsteal(ta_parent, ptr) (TA_TYPEOF(ptr))ta_xsteal_(ta_parent, ptr)
 #define ta_xrealloc(ta_parent, ptr, type, count) \
     (type *)ta_xrealloc_size(ta_parent, ptr, ta_calc_array_size(sizeof(type), count))
 
 // Can't be macros, because the OOM logic is slightly less trivial.
 char *ta_xstrdup(void *ta_parent, const char *str);
 char *ta_xstrndup(void *ta_parent, const char *str, size_t n);
-void *ta_xsteal_(void *ta_parent, void *ptr);
 void *ta_xmemdup(void *ta_parent, void *ptr, size_t size);
 void *ta_xrealloc_size(void *ta_parent, void *ptr, size_t size);
 

ta/ta_talloc.h

@@ -34,7 +34,7 @@
 #define talloc_ptrtype                  ta_xnew_ptrtype
 #define talloc_array_ptrtype            ta_xnew_array_ptrtype
 
-#define talloc_steal                    ta_xsteal
+#define talloc_steal                    ta_steal
 #define talloc_realloc_size             ta_xrealloc_size
 #define talloc_new                      ta_xnew_context
 #define talloc_set_destructor           ta_set_destructor

ta/ta_utils.c

@@ -53,8 +53,6 @@ void *ta_new_context(void *ta_parent)
 
 /* Set parent of ptr to ta_parent, return the ptr.
  * Note that ta_parent==NULL will simply unset the current parent of ptr.
- * If the operation fails (on OOM), return NULL. (That's pretty bad behavior,
- * but the only way to signal failure.)
  */
 void *ta_steal_(void *ta_parent, void *ptr)
 {
@@ -288,12 +286,6 @@ char *ta_oom_s(char *s)
     return s;
 }
 
-void *ta_xsteal_(void *ta_parent, void *ptr)
-{
-    ta_set_parent(ptr, ta_parent);
-    return ptr;
-}
-
 void *ta_xmemdup(void *ta_parent, void *ptr, size_t size)
 {
     void *new = ta_memdup(ta_parent, ptr, size);