[PATCH] Don't declare __malloc_check_init in <malloc.h> (bug 23352)

[Florian Weimer]

* Andreas Schwab:

> The function was never part of the malloc API.
>
> 	[BZ #23352]
> 	* malloc/malloc.h (__malloc_check_init): Don't declare.
> 	* include/malloc.h (__malloc_check_init): Likewise.
> 	* malloc/malloc-internal.h (__malloc_check_init): Declare it here.
> 	* manual/memory.texi (__malloc_check_init): Don't mention it.

Looks good to me.

Thanks,
Florian